Comparison of dragonfly algorithm and Harris hawks optimization evolutionary data mining techniques for the assessment of bearing capacity of footings over two-layer foundation soils

Engineering with Computers - By assist of novel evolutionary science, the classification accuracy of neural computing is improved in analyzing the bearing capacity of footings over two-layer...     

CSCNN: Cost-Sensitive Convolutional Neural Network for Encrypted Traffic Classification

Neural Processing Letters - By the rapid development of the Internet and online applications, traffic classification not only has changed to an interesting topic in the field of computer networks...     

Thermal performance analysis of arbitrary-profile fins with non-fourier heat conduction behavior

The thermal performance of variable cross-section fins is considered using the Maxwell–Cattaneo–Vernotte (MCV) heat conduction model. Four different fins, namely rectangular, triangular, convex, and concave fins, with a periodic thermal condition are examined. The governing equations are hyperbolic and are solved numerically using an implicit finite difference method. In the MCV model, the thermal wave propagates with a finite speed, and hence sharp discontinuities appear in the temperature profiles. In this study, temperature profiles at various times, heat transfer rates, and thermal efficiencies of Fourier and non-Fourier fins are presented. In addition, the effect of relaxation time is considered. The results show that the effects of cross-sectional area and relaxation time are considerable on the thermal performance of various non-Fourier fins. To validate our findings, the results for non-Fourier fins with constant cross-sectional area obtained from this study are compared to those of other numerical solutions. This comparison confirms the correctness of the current results.     

A compensated PID active queue management controller using an improved queue dynamic model

Beside the major objective of providing congestion control, achieving predictable queuing delay, maximizing link utilization, and robustness are the main objectives of an active queue management (AQM) controller. This paper proposes an improved queue dynamic model while incorporating the packet drop probability as well. By applying the improved model, a new compensated PID AQM controller is developed for Transmission Control Protocol/Internet Protocol (TCP/IP) networks. The non‐minimum phase characteristic caused by Padé approximation of the network delay restricts the direct application of control methods because of the unstable internal dynamics. In this paper, a parameter‐varying dynamic compensator, which operates on tracking error and internal dynamics, is proposed to not only capture the unstable internal dynamics but also reduce the effect of uncertainties by unresponsive flows. The proposed dynamic compensator is then used to design a PID AQM controller whose gains are obtained directly from the state‐space representation of the system with no further gain tuning requirements. The packet‐level simulations using network simulator (ns2) show the outperformance of the developed controller for both queuing delay stability and resource utilization. The improved underlying model leads also to the faster response of the controller. Copyright © 2013 John Wiley & Sons, Ltd.     

Microstructure and mechanical properties of dual phase steels,with different martensite morphology,produced during TLP bonding of a low C-Mn steel

In this research, production of ferrite - martensite dual phase Steels with different martensite morphology was considered during transient liquid phase bonding of a low carbon steel. The steel was bonded using an iron base interlayer with melting point of 1443 K and 40 μm thickness. Bonding process carried out at 1473 K, under pressure of 0.5 MPa, at different holding time of 10, 20, 30 and 40 minutes. Microstructural studies of joint region showed that isothermal solidification completed at the bonding time of 40 minutes. Microstructure of joints made at the bonding time of 10, 20, and 30 minutes consists of two distinct region, athermal and isothermal solidified zones. Microstructure of these zones was studied and chemical composition of these zones was determined by EDS. Joints made with bonding time of 40 minutes were homogenized at 1008 K and then cooled into cold water to produce dual phase ferrite and martensite microstructure with different martensite morphology. According to shear test results, it was found that the shear strength of ferrite - fibrous martensite microstructure is greater than those with ferrite - continuous martensite and ferrite - blocky martensite microstructure.     

Nanofiber films of chloroacetated natural rubber/poly(vinyl alcohol) by electrospinning technique: Silica effects on biodegradation

Green electrospinning technique was employed to prepare chloroacetated natural rubber (CNR)/poly(vinyl alcohol) (PVA) nanofiber films by varying the addition of PVA in the range 2.5–55 wt % followed by encapsulation of 2.5 wt % fumed silica (FS). In this study, the risk of using organic solvents was eliminated using CNR in latex. The encapsulated electrospun fiber mats showed a fairly homogenous composition with enhanced water absorption ability of 703.54% ± 33.95%. The FS improved the interfacial adhesion and contributed to enhancing the intermolecular interaction between the two polymers. The mean diameter of the nanofibers decreased from 64.0 ± 19.0 to 41.0 ± 13.0 nm and significant improvement in the hydrolytic and enzymatic degradation rate was observed implying that FS can facilitate the degradation rate. Furthermore, loading of PVA and encapsulation of FS resulted in an improved stiffness of CNR at room temperature and storage modulus increased to 2.48 and 2.12 MPa, respectively. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46432.     

Toward an intelligent approach for predicting surface tension of binary mixtures containing ionic liquids

Knowledge of the surface tension of ionic liquids (ILs) and their related mixtures is of central importance and enables engineers to efficiently design new processes dealing with these fluids on an industrial scale. It’s obvious that experimental determination of surface tension of every conceivable IL and its mixture with other compounds would be a herculean task. Besides, experimental measurements are intrinsically laborious and expensive; therefore, accurate prediction of the property using a reliable technique would be overwhelmingly favorable. To do so, a modeling method based on artificial neural network (ANN) trained by Bayesian regulation back propagation training algorithm (trainbr) has been proposed to predict surface tension of the binary ILs mixtures. A total set of 748 data points of binary surface tension of IL systems within temperature range of 283.1-348.15 K was used to train and test the applied network. The obtained results indicated that the predictive values and experimental data are quite matching, representing reliability of the used ANN model for such purpose. Also, compared with other methods, such as SVM, GA-SVM, GA-LSSVM, CSA-LSSVM, GMDH-PNN and ANN trained with trainlm algorithm the proposed model was better in terms of accuracy.     

Energy efficiency: The bird’s-eye view

If energy efficiency policy works, it should be possible to detect its effect on aggregate demand. The article integrates ideas from conventional methods for forecasting electricity demand to build a model to investigate the relationship between per person electricity use and energy efficiency policies. The model is then estimated with historical data on 50 states and the District of Columbia to evaluate the effect of publicly funded energy efficiency.     

Investigation on local and average static hold‐ups in liquid–liquid systems in a rotary disc contactor

A rotating disc contactor with inner diameter of 91 mm and 21 compartments was used to investigate local and average static hold‐ups in the column. Three chemical systems, including distilled water as stagnant continuous phase and toluene, kerosene, and butyl acetate as dispersed phase, in case of no mass transfer, were applied. Different parameters consisting of drop size and static hold‐up were measured experimentally under various operating conditions, and two dimensionless correlations for estimation of local static hold‐up as a function of average mother drop size, physical properties, rotor speed, and stage number were proposed in two cases: (1) immovable and (2) rotating rotor discs. Furthermore, two dimensionless correlations were presented to estimate average static hold‐up as a function of average mother drop size, physical properties, rotor speed, and number of stages in the column in the two aforementioned conditions.