Semantic Interoperability of Heterogeneous Semantic Resources

This paper presents a three-step approach to enhance interoperability between heterogeneous se- mantic resources. Firstly, we construct homogeneous representations of these resources in a pivot format, namely OWL DL, with respect to the semantics expressed by the original representation languages. Secondly, mappings are established between concepts of these standardised resources and stored in a so-called articulation ontology. Thirdly, an approach for ranking those mappings is suggested in order to best fit users' needs. This approach is currently being implemented in the Semantic Resources “Interoperabilisation” and Linking System (SRILS). The mapping results as well as the work to be done are discussed.     

Scenario Assessment of Streamflow Simulation and its Transition Probability in Future Periods Under Climate Change

The effect of climate change on water resources is an important challenge. To analyze the negative effects of this phenomenon and recommend adaptive measures, it is necessary to assess streamflow simulation scenarios and streamflow transition probabilities in future periods. This paper employs the HadCM3 (Hadley Centre Coupled Model, version 3) model to generate climate change scenarios in future periods (2010–2039, 2040–2069, and 2070–2099) and under A2 emission scenarios. By introducing climatic variable time series in future periods to the IHACRES (Identification of unit Hydrographs And Component flows from Rainfall, Evaporation and Streamflow data) hydrological model, long-term streamflow simulation scenarios are produced. By fitting statistically different distributions on runoff produced by using goodness-of-fit tests, the most appropriate statistical distribution for each month is chosen and relevant statistical parameters are extracted and compared with statistical parameters of runoff in the base period. Results show that long-term annual runoff average in the three future periods compared to the period 2000–1971 will decrease 22, 11, and 65 %, respectively. ?Despite the reduction in total runoff volume in future periods compared to the baseline period, the decrease is related to medium and high flows. In low flows, total runoff volumes for future periods compared to the baseline period will increase 47, 41, and 14 %, respectively. To further assess the impact of annual average runoff on flows, it is necessary to examine the correlation of time series using streamflow transition probabilities. To compare the streamflow transition probability in each of the future periods with base period streamflow in each month, streamflow is discretized and performance criteria are used. Results show a low coefficient of correlation and high error indicators.     

Dye Adsorption on Cubic Polyhedral Oligomeric Silsesquioxane-Based Poly(acrylamide-<Emphasis Type="Italic">co</Emphasis>-itaconic acid) Hybrid Nanocomposites: Kinetic,Thermodynamic and Isotherms Studies

In the present study, poly(acrylamide-co-itaconic acid) hybrid nanocomposites were synthesized via free radical copolymerization method. Octavinyl polyhedral oligomeric silsesquioxane (OV-POSS) with different weight ratio (0, 4, 8, 12 and 14 wt%) was utilized as a cross-linker. Dye adsorption properties of the as-prepared hybrid nanocomposites were investigated for crystal violet (CV) elimination from aqueous solution. The effect of various parameters, such as OV-POSS content, adsorbent amount, pH, temperature, contact time and initial dye concentration, on the adsorption of CV was studied. Moreover, adsorption kinetic, isotherm and the thermodynamic of the CV adsorption on the so-called hybrid nanocomposites were studied.     

Challenges of working with artifacts in requirements engineering and software engineering

When developing or evolving software systems of non-trivial size, having the requirements properly documented is a crucial success factor. The time and effort required for creating and maintaining non-code artifacts are significantly influenced by the tools with which practitioners view, navigate and edit these artifacts. This is not only true for requirements, but for any artifacts used when developing or evolving systems. However, there is not much evidence about how practitioners actually work with artifacts and how well software tools support them. Therefore, we conducted an exploratory study based on 29 interviews with software practitioners to understand the current practice of presenting and manipulating artifacts in tools, how practitioners deal with the challenges encountered, and how these challenges affect the usability of the tools used. We found that practitioners typically work with several interrelated artifacts concurrently, less than half of these artifacts can be displayed entirely on a large screen, the artifact interrelationship information is often missing, and practitioners work collaboratively on artifacts without sufficient support. We identify the existing challenges of working with artifacts and discuss existing solutions proposed addressing them. Our results contribute to the body of knowledge about how practitioners work with artifacts when developing or evolving software, the challenges they are faced with, and the attempts to address these challenges.     

Impact-Based Nonlinear Acoustic Testing for Characterizing Distributed Damage in Concrete

Nonlinear acoustics-based nondestructive evaluation (NDE) techniques have shown great promise for identification of microstructure and microcracking in a wide spectrum of materials (e.g., metals, metallic alloys, composites, rocks, cementitious materials). This class of NDE techniques relies on measuring nonlinearity parameters by analyzing the acoustic response of materials that are dynamically perturbed at microstrain levels (strain \(\sim \)10\(^{-6}\)–10\(^{-5})\). Using a mechanical impact to induce microstrain is advantageous for concrete testing because it allows for testing of larger concrete specimens offering potential field transportability. In this paper, two impact-based nonlinear acoustic testing techniques are compared: impact-based nonlinear resonant acoustic spectroscopy (INRAS) and dynamic acousto-elastic testing (IDAET). INRAS gives a global measure of sample hysteretic nonlinearity while IDAET provides a local but comprehensive account of nonlinear elastic properties. We discuss single- versus multi-impact INRAS and propose a physics-based model to describe the data from single-impact INRAS. Then, we introduce IDAET and demonstrate how to extract both classical and non-classical nonlinear parameters from a limited set of test results. INRAS and IDAET are used to monitor the evolution of damage in two sets of concrete samples undergoing freeze-thaw (FT) cycles. Nonlinear parameters extracted from the two tests show good agreement; all exhibiting far more sensitivity to distributed FT damage than standard (i.e. linear) resonance frequency measurements. By presenting alternative ways to collect and analyze the impact-based nonlinear acoustic test data, this study will help in broadening their use and extending their applications to quantitative in-situ evaluation.     

New formulations for the setup assembly line balancing and scheduling problem

We present three new formulations for the setup assembly line balancing and scheduling problem (SUALBSP). Unlike the simple assembly line balancing problem, sequence-dependent setup times are considered between the tasks in the SUALBSP. These setup times may significantly influence the station times. Thus, there is a need for scheduling the list of tasks within each station so as to optimize the overall performance of the assembly line. In this study, we first scrutinize the previous formulation of the problem, which is a station-based model. Then, three new formulations are developed by the use of new sets of decision variables. In one of these formulations, the schedule-based formulation, SUALBSP is completely formulated as a scheduling problem. That is, no decision variable in the model directly denotes a station. All the proposed formulations will be improved by the use of several enhancement techniques such as preprocessing and valid inequalities. These improved formulations can be applied to establishing lower bounds on the problem. To assess the performance of new formulations, results of an extensive computational study on the benchmark data sets are also reported.     

CO<Subscript>2</Subscript>/O<Subscript>2</Subscript>-oxidative dehydrogenation of ethane to ethylene over highly dispersed vanadium oxide on MgO-promoted sulfated-zirconia nanocatalyst: Effect of sulfation on catalytic properties and performance

The ZrO₂ was treated by various molarities of H₂SO₄ solution (0, 0.5, 1 and 2) then mixed by MgO and impregnated with 5 wt% of V₂O₅. The synthesized catalysts were characterized by XRD, FESEM, PSD, EDX, BET and FTIR techniques. According to the results obtained by characterization studies, the modification of MgO-ZrO₂ support by various molarities of H₂SO₄ solution had a great impact on the crystallinity, morphology and functional groups of prepared nanocatalysts. On the other hand, the catalytic activity of synthesized nanocatalysts in the oxidative dehydrogenation of ethane to ethylene is affected by the sulfur content on the support. The crystalline structures of MgO and ZrO₂ were confirmed by XRD analysis. The crystallinity of tetragonal ZrO₂ was decreased by increasing H₂SO₄ molarity used in ZrO₂ (Sx) synthesising. The highest catalytic performance and ethylene productivity (C₂H₄ yield of 48% and ethane conversion of 79% at 700 °C) were obtained on the V₂O₅/MgO-ZrO₂ (S1) nanocatalyst. This could be related to the superior acid-base property, smaller particles, better dispersion of active phase and uniform morphology of V₂O₅/MgO-ZrO₂ (S1).     

Preparation of hydrophilic dimethyl 5‐sodium sulfoisophthalate/poly(ethylene terephthalate) nanofiber composite membranes for improving antifouling properties

In this study, the effect of dimethyl 5‐sodium sulfoisophthalate (SSI) nanoparticles (NPs) on the antifouling properties of poly(ethylene terephthalate) (PET) electrospun nanofiber membranes (ENMs) was investigated through the ultrafiltration of C. I. Basic Blue 3. 3 dye. To reveal the tortuous effect of this additive on the antifouling properties, scanning electron microscopy was used for the characterization of the ENM structure and the optimization of the SSI NP content. Then, some selected physical and structural properties of the membrane, such as the porosity, moisture regain, contact angle, hydraulic permeability (L _p ), and mechanical properties, in the optimized range of SSI NP contents were investigated. Finally, the influence of this additive on the rejection and flux recovery ratio of the prepared membranes was considered. Consequently, the antifouling properties were assessed with consideration of all of the aforementioned parameters. The SSI/PET2 membrane (that with 0.02% w/w SSI NPs with respect to the total amount of PET polymer and SSI NPs), with an average nanofiber diameter of 450 nm, a porosity of 78.44%, a moisture regain of 9.34%, a contact angle of 86.48°, an L _p of 42,167 L h^?1 m^?2 bar^?1, a tensile strength of 4.66 ± 0.04 MPa, a flux recovery ratio of 15.3%, and a final rejection of 95%, showed a significant enhancement in the antifouling properties compared with pristine PET ENMs. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44522.