Using discussion logic in analyzing online group discussions: A text mining approach

We propose a Discussion Logic-based Text Analytics (DiLTA) framework, which combines theories developed in social science and text mining fields. The framework extracts features that uncover discussion logic and uses these features in analyzing online discussions. A series of models are proposed including conversation disentanglement, coherence analysis, and visualization. Validation experiments showed that DiLTA achieved significantly superior performance over existing text analytics methods in reconstructing internal structure. A case study using DiLTA-enabled visualization on a healthcare forum illustrates the great potential of DiLTA in assisting comprehension of the internal linkage, structure, and logic of online group discussions.     

Configurable FFT Processor Using Dynamically Reconfigurable Resource Arrays

This paper presents results of using a Coarse Grain Reconfigurable Architecture called DRRA (Dynamically Reconfigurable Resource Array) for FFT implementations varying in order and degree of parallelism using radix-2 decimation in time (DIT). The DRRA fabric is extended with memory architecture to be able to deal with data-sets much larger than what can be accommodated in the register files of DRRA. The proposed implementation scheme is generic in terms of the number of FFT point, the size of memory and the size of register file in DRRA. Two implementations (DRRA-1 and DRRA-2) have been synthesized in 65 nm technology and energy/delay numbers measured with post-layout annotated gate level simulations. The results are compared to other Coarse Grain Reconfigurable Architectures (CGRAs), and dedicated FFT processors for 1024 and 2048 point FFT. For 1024 point FFT, in terms of FFT operations per unit energy, DRRA-1 and DRRA-2 outperforms all CGRA by at least 2× and is worse than ASIC by 3.45×. However, in terms of energy-delay product DRRA-2 outperforms CGRAs by at least 1.66× and dedicated FFT processors by at least 10.9×. For 2048-point FFT, DRRA-1 and DRRA-2 are 10× better for energy efficiency and 94.84 better for energy-delay product. However, radix-2 implementation is worse by 9.64× and 255× in terms of energy efficiency and energy-delay product when compared against a radix-2⁴ implementation.

     

New approach to mimic rheological actual shear rate under wall slip condition

Engineering with Computers - The presence of wall slip in concentrated suspensions affect the rheological measurements such as shear stress, shear rate, and viscosity. The measured shear rate will...     

Energy efficient scheduling in local area networks

Wireless Networks - In Wireless Local Area Networks (WLAN), portable devices such as notebooks, tabs, and smart phones are powered by batteries with limited energy. With the great increase of using...     

Aging of novel membranes made of PVA and cellulose nanocrystals extracted from Egyptian rice husk manufactured by compression moulding process

Novel membranes consisting of polyvinyl alcohol (PVA), cellulose nanocrystals (CNCs) originated from Rice Husk (RH), Glutaraldehyde (GLA) and Glycerine (G) were manufactured by the compression moulding process. Rice husk is a new source to isolate pure cellulose nanocrystals via mechanical and chemical treatment. The biodegradability of the membranes has been evaluated using UV accelerated weathering as well as a soil burial test. The morphology of membranes (PVA/RH-CNCs) was characterized by using the Scanning Electron Microscope (SEM). The chemical structure of the membranes (PVA/RH-CNCs) was characterised by Fourier-Transformation Infrared (FTIR) spectroscopy as well as wide-angle X-ray diffraction. The mechanical properties of the membranes were evaluated using standard techniques. Swelling and weight loss resulting from biodegradation were also evaluated. The results showed that the developed transient membranes can be used as food packaging bags owing to biodegradability (weight loss) under irradiation and during soil burial.     

Recursive least squares estimation methods for a class of nonlinear systems based on non-uniform sampling

Many dynamic processes in practice have nonlinear characteristics and must be described by using nonlinear models. It remains to be a challenging problem to build the models of such nonlinear systems and to estimate their parameters. This article studies the parameter estimation problem for a class of Hammerstein-Wiener nonlinear systems based on non-uniform sampling. By means of the auxiliary model identification idea, an auxiliary model-based recursive least squares algorithm is derived for the systems. In order to enhance the computational efficiency, an auxiliary model-based hierarchical least squares algorithm is proposed by utilizing the hierarchical identification principle. The simulation results confirm the effectiveness of the proposed algorithms.     

Full and reduced-order H∞ filtering of Takagi–Sugeno fuzzy time-varying delay systems: Input–output approach

This article addresses the issue of delay-dependent H_∞ filtering design for TakagiŮSugeno fuzzy time-varying delay systems using the input–output approach. A three-term approximation model has been used to transform the original system into two interconnected subsystems. Since the nonquadratic Lyapunov–Krasovskii functional requires to deal with the membership function's (MF) time derivative, upper-bound inequalities have been added to the obtained conditions. Based on the scaled small gain theorem, nonquadratic Lyapunov–Krasovskii functional approach and considering the bounds of the MF time-derivative, the H_∞ full- and reduced-order filters are designed and then formulated in terms of linear matrix inequalities. Finally, illustrative examples are presented to demonstrate the validity of the proposed methods.     

Electro-osmotic flow of fractional second-grade fluid with fractional Cattaneo heat flux through a vertical microchannel

This study investigates the unsteady electro-osmotic flow (EOF) of a fractional second-grade fluid through a vertical microchannel with convection heat transfer. The fractional Cattaneo heat flux model will be used to modify the heat equation. The solutions for the velocity and the temperature have been derived by employing the Laplace and finite Fourier sine transforms and their numerical inverses. The results show that at the beginning of the time period, the fractional parameter postpones the movement of the fluid. Furthermore, the results show that at the high values of retardation time (non-Newtonian case), the required time for the velocity and the flow rate to reach the steady state increases. Moreover, the heat relaxation time reduces the heat transfer until a critical time, and then the effect reverses.