Lateral pull-in instability of electrostatic MEMS transducers employing repulsive force

Nonlinear Dynamics - We report on the lateral pull-in in capacitive MEMS transducers that employ a repulsive electrostatic force. The moving element in this system undergoes motion in two...     

Adsorption and degradation of methyl parathion (MP), a toxic organophosphorus pesticide,using NaY/Mn0.5Zn0.5Fe2O4 nanocomposite

Research on Chemical Intermediates - In this research, the applicability of NaY/Mn0.5Zn0.5Fe2O4 as a new synthesized nanocomposite adsorbent for the adsorption and degradation of methyl parathion...     

One-step, synthesis of Hantzsch esters and polyhydroquinoline derivatives using new organocatalyst

<正>Herein we report an efficient organocatalyst for the multicomponent Hantzsch reaction under mild condition.The product easily isolated by simple filtration and catalyst can be recovered.     

Analytical and Experimental Study to Predict the Residual Resistance Factor on Polymer Flooding Process in Fractured Medium

The major objectives of this study are to analytically and experimentally determine the residual resistance factor in the fractured medium based on the polymer solution properties and operational conditions. The parameters considered in this study are the polymer concentration, power law constitutive equation parameter, and salt concentration, sulfonation content of polymer, temperature, and molecular weight of the water soluble polymers which are used in polymer flooding for enhanced oil recovery. The results indicated that residual resistance factor in fractured medium is dependent on the coil overlap parameter and power law equation parameter of polymer. The coil overlap parameter is a dimensionless number consists of intrinsic viscosity and polymer concentration. Since intrinsic viscosity is a function of polymer diameter in medium conditions, to predict the residual resistance factor in fracture medium, an experimental correlation is generated for determination of the molecular diameter of polymer based on polymer molecular weight, temperature, salt concentration, and sulfonation content.     

The hp-d version of the finite cell method with local enrichment for multiscale problems

The finite cell method is extended to enable the computation of solids consisting of heterogeneous materials. The approach is based on a domain decomposition utilizing the hp-d method. Our results reveal that the proposed method improves the accuracy of the finite cell method significantly. It also paves the way for combining the finite cell method with other approaches like partition of unity based methods which can be of interest in many cases, such as dealing with composites and numerical homogenization. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

An extended compromise ratio model with an application to reservoir flood control operation under an interval-valued intuitionistic fuzzy environment

This paper presents a novel multiple attribute group decision-making (MAGDM) model based on the compromise ratio method under an interval-valued intuitionistic fuzzy (IVIF) environment. The compromise ratio method under uncertainty is introduced by a group of experts based on the concept that the chosen alternative should be as close as possible to the IVIF-positive-ideal point and as far away from the IVIF-negative-ideal point as possible concurrently. First, an IVIF-weighted geometric averaging (IVIFWGA) operator is employed to aggregate all individual IVIF-decision matrices provided by a group of experts into a collective IVIF-decision matrix. Two new basic IVIF-operations are introduced to handle the evaluation process. Then, an extended collective index in an IVIF environment is proposed to discriminate among alternatives for the evaluation process in terms of subjective and objective information. Finally, to demonstrate the suitability and applicability of the proposed IVIF-MAGDM model, an application example of reservoir flood control operation is given from the recent literature.     

Efficient computation of cellular materials using the finite cell method

The application of cellular materials in lightweight structures is a subject of growing interest. As meshing with surface aligned elements is very time consuming and entails a lot of degrees of freedom, we apply the finite cell method (FCM). The FCM is an extension of the known fictitious domain methods based on using high order polynomials for the Ansatz functions. In order to obtain a realistic representation of the geometry, we derive our discretization directly from the voxel data coming from the computer tomography (CT-scan) of the specimen of interest. Thus, a much coarser Cartesian grid consisting of hexahedral cells can be readily generated in a fully automated fashion. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)