Decision support for the software product line domain engineering lifecycle

Software product line engineering is a paradigm that advocates the reusability of software engineering assets and the rapid development of new applications for a target domain. These objectives are achieved by capturing the commonalities and variabilities between the applications of the target domain and through the development of comprehensive and variability-covering feature models. The feature models developed within the software product line development process need to cover the relevant features and aspects of the target domain. In other words, the feature models should be elaborate representations of the feature space of that domain. Given that feature models, i.e., software product line feature models, are developed mostly by domain analysts by sifting through domain documentation, corporate records and transcribed interviews, the process is a cumbersome and error-prone one. In this paper, we propose a decision support platform that assists domain analysts throughout the domain engineering lifecycle by: (1) automatically performing natural language processing tasks over domain documents and identifying important information for the domain analysts such as the features and integrity constraints that exist in the domain documents; (2) providing a collaboration platform around the domain documents such that multiple domain analysts can collaborate with each other during the process using a Wiki; (3) formulating semantic links between domain terminology with external widely used ontologies such as WordNet in order to disambiguate the terms used in domain documents; and (4) developing traceability links between the unstructured information available in the domain documents and their formal counterparts within the formal feature model representations. Results obtained from our controlled experimentations show that the decision support platform is effective in increasing the performance of the domain analysts during the domain engineering lifecycle in terms of both the coverage and accuracy measures.     

Optimization of Cu(II)-ion imprinted nanoparticles for trace monitoring of copper in water and fish samples using a Box–Behnken design

We describe a nanoparticles ion-imprinted polymer (IIP) for the selective preconcentration of copper (II) ions. It was obtained by precipitation polymerization from 2-vinylpyridine (the functional monomer), ethylene glycol dimethacrylate (the cross-linker), 2,2′-azobisisobutyronitrile (the initiator), 2,9-dimethyl-1,10-phenanthroline (the copper-binding ligand) and nickel nitrate (the template ion) in acetonitrile solution. The IIP particles were characterized by Fourier Transformed Infra Red Spectroscopy (FTIR), thermogravimetric and differential thermal analysis, and by scanning electron microscopy. The optimization process was carried out using the Box–Behnken design (BBD). Effects of several factors such as solution pH for adsorption, amount of polymer, type, concentration and volume of eluent for extraction, as well as adsorption and desorption times were investigated. Under the optimum conditions (type and concentration of eluent, HCl 1.6 mol L^?1; volume of eluent, 6 mL; adsorption solution pH, 6.0; amount of polymer, 30 mg; adsorption time, 25 min; desorption time, 25 min), preconcentration factor of the proposed method was approximately 100. Under the optimized conditions, the detection limit was found to be 0.1 μg L^?1, while the relative standard deviation (RSD) for six replicate measurements was calculated to be <4%.     

Immobilized iron Schiff base histidine complexes on Al-MCM-41 and zeolite Y as catalyst for oxidation of cycloalkanes

Iron complexes of N-salicylidene-l-histidine with or without bipyridine ligand immobilized on Al-MCM-41 and zeolite Y designated as Fe(sal-l-his)(bipy)complex/Al-MCM-41 or Fe(sal-l-his)complex/Al-MCM-41 and Fe(sal-l-his)(bpy)complex/Y or Fe(sal-l-his)complex/Y respectively, were prepared and characterized by X-ray powder diffraction (XRD), FT-IR, N₂ adsorption/desorption and chemical analysis techniques. Fe(sal-l-his)/Al-MCM-41 and Fe(sal-l-his)(bipy)complex/Al-MCM-41 were found to successfully catalyze the oxidation of cyclohexane, methyl cyclohexane, cyclooctane and adamantane with H₂O₂. The oxidation results and promising catalytic behavior of Fe(sal-l-his)(bipy)complex/Al-MCM-41 for oxidation of cyclooctane with 90 % conversion and excellent selectivity toward the formation of cyclooctanone will be discussed in this presentation.     

Morphological investigation of synthetic poly(amic acid)/cerium oxide nanostructures

A new kind of intermediate hybrid nanocomposites (NCs) composed of poly(amic acid) (PAA) and surface modified ceria nanoparticles (NP)s had been prepared by sonochemical assisted synthesis. The PAA containing pendent benzamide units had been synthesized by the reaction of 3,5‐diamino‐N‐(4‐hydroxyphenyl) benzamide and benzene‐1,2,4,5‐tetracarboxylic dianhydride through polycondensation reaction. The structure of the prepared PAA was studied by spectroscopic techniques. The surface modifications of ceria NPs were achieved by using hexadecyltrimethoxysilane. Results of FTIR analysis demonstrated that the aliphatic chains have been covalently bonded to the surface of the CeO₂ NPs. PAA/CeO₂ NCs with different contents including 4, 8, and 12 wt% of CeO₂ NPs was prepared by using sonochemical method. Characterization with FTIR, powder X‐ray diffraction, field emission scanning electron microscopy (FE‐SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) confirmed the success in synthesis of NCs with well dispersion properties. XRD analysis results showed that the obtained NCs displayed the crystalline nature of ceria NPs and the amorphous character of PAA matrix. The particles size of ceria NPs in NCs are about 50–70 nm as characterized by FE‐SEM, TEM, and AFM analyses. This work demonstrates the application of intermediates as new matrices for preparation of hybrid nanostructures. POLYM. ENG. SCI., 55:2339–2348, 2015. © 2015 Society of Plastics Engineers     

In-vitro formation and growth kinetics of apatite on a new light-cured composite calcium phosphate cement

Calcium phosphate cements are used as synthetic bone grafts with several advantages such as biocompatibility, osteoconductivity, and moldability. In this study, the synthesis of a biocement starting from calcium hydroxide (Ca(OH)₂) and Monocalcium Phosphate Monohydrate (MCPM) was investigated. A 6?wt% Na₂HPO₄ aqueous solution along with a modified polymeric resin (RIVA(SDI)^®) were adopted as the variable liquid phase in self- and light-cure cement groups. XRD analysis and FTIR spectroscopy were used to study the phase composition. The composite microstructure was characterized by scanning electron microscopy (SEM) and the degradation rates were measured by atomic absorption spectroscopy (AAS) analysis. In addition, the effect of soaking time of the cement in simulated body fluid (SBF) on the final phase and morphology was studied. The results showed that soaking the composite in SBF has a significant influence in phase transformation into hydroxyapatite, but following a slower kinetic in light-cured composite cements. Evidences of crosslinking reactions in light-cured cements were observable, which at the same time can legitimize slower apatite formation and faster biodegradation of these composite cements.     

Synthesis and characterization of polyethylene glycols conjugated to polybutylcyanoacrylate nanoparticles

This study aimed to evaluate the cytotoxicity effects of various polyethylene glycols (PEGs), and construction and characterization of polybutylcyanoacrylate (PBCA) nanoparticles. Cytotoxicity was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay on rat glioma C6 cell line, and PBCA nanoparticles were prepared by emulsion polymerization method. Also, the nanoparticles were characterized by dynamic light scattering and scanning electron microscopy. The findings showed that PEGs were approximately safe and cytotoxicity was inversely proportional with their molecular weights. In addition, the size of nanoparticles were increased with reducing molecular weights of PEGs. PEGs with negligible cytotoxicity and stabilizing functionality were demonstrated in this study.     

Statistical process control using optimized neural networks: A case study

The most common statistical process control (SPC) tools employed for monitoring process changes are control charts. A control chart demonstrates that the process has altered by generating an out-of-control signal. This study investigates the design of an accurate system for the control chart patterns (CCPs) recognition in two aspects. First, an efficient system is introduced that includes two main modules: feature extraction module and classifier module. In the feature extraction module, a proper set of shape features and statistical feature are proposed as the efficient characteristics of the patterns. In the classifier module, several neural networks, such as multilayer perceptron, probabilistic neural network and radial basis function are investigated. Based on an experimental study, the best classifier is chosen in order to recognize the CCPs. Second, a hybrid heuristic recognition system is introduced based on cuckoo optimization algorithm (COA) algorithm to improve the generalization performance of the classifier. The simulation results show that the proposed algorithm has high recognition accuracy.     

Catalytic effect of hydrogen chloride on the degradation of poly(vinyl chloride)

The distribution of polyenes which results from the chemical dehydrochlorination of poly(vinyl chloride) has been studied in dichloromethane (DCM) and tetrahydrofuran (THF) solvents. A higher percentage of longer polyenes is formed in DCM than in THF. On the addition of trifluoroacetic acid to DCM solutions of the polyenes, new species are formed with strong absorptions in the region 500–800 nm. The absorptions are probably due to polyenylic ions formed by protonation of the polyenes, and the interrelated changes in their intensities can be explained by the migration of short polyene sequences along the polymer chain with the formation of longer sequences. The species are extremely photosensitive and are bleached in a few seconds with light from a medium-pressure mercury lamp. The relevance of these experiments to the effect of HCl on the polyene distribution and on the rate of photocrosslinking is discussed.     

Efficient cooperative multicarrier underwater acoustic communication over the Persian Gulf channel

Real-time and reliable transmission with high data rate is one of the most crucial design issues in underwater acoustic (UWA) communications. This paper is part of an operational project in the Persian Gulf which is known as a shallow water channel worldwide. Building on the promising combination of cooperative and multicarrier techniques, we first address the design of an efficient UWA communication system over the Persian Gulf channel. We assume sparse and frequency-selective Rician fading, non-white correlated Gaussian ambient noise, and non-uniform Doppler distortion among subcarriers. Based on the extensive field measurements, we adopt a comprehensive channel model including modified sound speed profile, modified absorption coefficient, reflections from the surface and bottom of the sea, and modified ambient noise model. In our work, carrier frequency is efficiently determined based on the system and environmental parameters. In addition, a simple criterion for Doppler scale calculation is proposed. Moreover, based on the approximate auto-correlation function of the ambient noise, whitening filter is utilized at the receiver. In many applications of underwater acoustic sensors network (UW-ASN), nodes may not be big enough to have more than one antenna. Therefore, to achieve spatial diversity, cooperation between nodes can be a proper alternate method. In another part of this research, toward a proper approach that each node operates under full-duplex mode, we address a cooperative virtually-aided transmission scenario which is called cooperative multiple input single output. Simulation results demonstrate that our proposed models can significantly improve the bit error rate performance of UW-ASN in the Persian Gulf channel.