A novel UV‐cured interpenetrating organic–inorganic hybrid polymer network based phase change materials (IPN‐PCM)

The purpose of this paper is to introduce a novel UV‐cured interpenetrating polymer networked phase change materials (IPN‐PCMs), on which no article has been found in the so far published research. Maleated castor oil (MCO) was synthesized via maleinization reaction of castor oil with maleic anhydride. Organic–inorganic hybrid interpenetrating polymer networked (IPN) materials containing both cationic and radical sections and IPN‐PCMs containing tetradecanol, hexadecanol, and octadecanol were prepared. The chemical structure of MCO and organic–inorganic hybrid IPN‐PCMs were determined by using Fourier Transform Infrared Spectroscopy (FT‐IR). Differential scanning calorimetry (DSC) was used for examining the phase‐change behaviors of the materials. Thermal stability was investigated by thermogravimetric analysis (TGA). Moreover, the surface formation of the specimen was investigated by scanning electron microscopy (SEM). In conclusion, our study proved that because of their high latent heat storage scope and high thermal stability, the obtained organic–inorganic hybrid IPN‐PCMs could be used as thermal energy storage materials. POLYM. ENG. SCI., 58:870–875, 2018. © 2017 Society of Plastics Engineers     

A novel permission-based Android malware detection system using feature selection based on linear regression

Neural Computing and Applications - With the developments in mobile and wireless technology, mobile devices have become an important part of our lives. While Android is the leading operating system...     

Synchronization analysis of coupled Lienard-type oscillators by averaging

Sufficient conditions for the synchronization of coupled Lienard-type oscillators are investigated via averaging technique. The coupling considered here is fixed, nonsymmetric, and nonlinear. Under the assumption that the interconnection topology defines a connected graph, it is shown that the solutions of oscillators converge arbitrarily close to each other, starting from initial conditions arbitrarily far apart, provided that the frequency of oscillations is large enough and the initial phases of oscillators all lie in an open semicircle. It is also shown that the nearly-synchronized oscillations always take place around some fixed magnitude independent of the initial conditions and the coupling functions.     

Robustness with dynamic IQCs: An exact state-space characterization of nominal stability with applications to robust estimation

For robustness analysis with integral quadratic constraints, we formulate a new positivity condition on the solution of the corresponding linear matrix inequality which is necessary and sufficient for nominal stability of the underlying system. The application of this technical result is illustrated by a complete solution of the L₂-gain and robust H₂-estimator design problems if the uncertainties are characterized by dynamic integral quadratic constraints.     

Remote-Controlled Ambidextrous Robot Hand Concept

In the development of robotic limbs, the side of members is of importance to define the shape of artificial limbs and the range of movements. It is mainly significant tbr biomedical applications concerning patients suffering arms or legs injuries, fn this paper, the concept of an ambidextrous design lbr robot hands is introduced. The fingers can curl in one xvay or another, to imitate either a right hand or a left hand. The advantages and inconveniences of different models have been investigated to optimise the range and the maximum force applied by fingers. Besides, a remote control interthce is integrated to the system, allowing both to send comrnands through internet and to display a video streaming of the ambidextrous hand as feedback. Therefore, a robotic prosthesis could be used for the first time in telerehabilitation. The main application areas targeted are physiotherapy alter strokes or management of phantom pains/br amputees by/earning to control the ambidextrous hand. A client application is also accessible on Facehook social network, making the robotic limb easily reachable for the patients. Additionally the ambidextrous hand can be used tbr robotics research as well as artistic performances.     

Characterizing interwell connectivity in waterflooded reservoirs using data-driven and reduced-physics models: a comparative study

Waterflooding is a significantly important process in the life of an oil field to sweep previously unrecovered oil between injection and production wells and maintain reservoir pressure at levels above the bubble-point pressure to prevent gas evolution from the oil phase. This is a critical reservoir management practice for optimum recovery from oil reservoirs. Optimizing water injection volumes and optimizing well locations are both critical reservoir engineering problems to address since water injection capacities may be limited depending on the geographic location and facility limits. Characterization of the reservoir connectivity between injection and production wells can greatly contribute to the optimization process. In this study, it is proposed to use computationally efficient methods to have a better understanding of reservoir flow dynamics in a waterflooding operation by characterizing the reservoir connectivity between injection and production wells. First, as an important class of artificial intelligence methods, artificial neural networks are used as a fully data-driven modeling approach. As an additional powerful method that draws analogy between source/sink terms in oil reservoirs and electrical conductors, capacitance–resistance models are also used as a reduced-physics-driven modeling approach. After understanding each method’s applicability to characterize the interwell connectivity, a comparative study is carried out to determine strengths and weaknesses of each approach in terms of accuracy, data requirements, expertise requirements, training algorithm and processing times.

     

Erratum to: Characterizing interwell connectivity in waterflooded reservoirs using data-driven and reduced-physics models: a comparative study

Neural Computing and Applications -     

Optimal regulation of homogeneous systems

We present an offline numerical algorithm to generate a discontinuous feedback law to robustly regulate the origin of a continuous-time homogeneous system through sample and hold. The proposed feedback comes out of the solution of an infinite horizon optimization problem in discrete time and is in the form of a look-up table. We show that when applied to either chained systems or systems in power form the algorithm results in a closed loop whose origin is globally exponentially stable.     

The effect of pre-polymer/cross-linker storage on the elasticity and reliability of PDMS microfluidic devices

Polydimethylsiloxane (PDMS) is a commonly used material in biomedical engineering (Sollier et al. in Lab Chip 11(22):3752–3765, 2011; Palchesko et al. in PLoS ONE 7(12):e51499, 2012; Berthier et al. in Lab Chip 12(7):1224–1237, 2012). Its elastic nature makes PDMS especially attractive for microfluidic large-scale integration (mLSI) technology where micromechanical valves are actuated by deflecting a PDMS membrane under pressure. Therefore, understanding and control of PDMS elastic properties have commercial and scientific significance. In this study, we have investigated the effects of pre-polymer/cross-linker storage conditions on the mechanical properties of cured PDMS films as well as on microfluidic devices. We have showed that when the uncured components of PDMS are exposed to different humidity conditions, the elasticity of the PDMS changes and this is revealed as a change in the Young’s modulus of the cured PDMS. The high humidity (~85%) exposure for 24 h causes PDMS to become softer as confirmed by a significant decrease in the Young’s modulus values from 1.2 to 0.9 MPa. Furthermore, as the PDMS is exposed to high humidity conditions for longer periods (72 h), the Young’s modulus decreases down to 0.7 MPa. We found that exposing only the pre-polymer PDMS (Part A) to humid air does not alter the cured PDMS properties significantly, whereas exposure of the cross-linker (Part B) is responsible for the elasticity change. We have strictly controlled the storage humidity to build more reliable microfluidic chips using mLSI. As a result, actuation pressure of valves (10 psi) and defects of devices (in <30% of chips) are significantly reduced. These results suggest that to improve the manufacturing yield and reliability of PDMS devices, storage humidity should be controlled immediately after the material synthesis.