Nature-inspired meta-heuristics approaches for charging plug-in hybrid electric vehicle

Currently, there is a remarkable focus on green technologies for taking steps towards more use of renewable energy sources within the sector of transportation and also decreasing pollution. At this point, employment of plug-in hybrid electric vehicles (PHEVs) needs sufficient charging allocation strategy, by running smart charging infrastructures and smart grid systems. In order to daily usage of PHEVs, daytime charging stations are required and at this point, only an appropriate charging control and a management of the infrastructure can lead to wider employment of PHEVs. In this study, four swarm intelligence based optimization techniques: particle swarm optimization (PSO), gravitational search algorithm (GSA), accelerated particle swarm optimization, and hybrid version of PSO and GSA (PSOGSA) have been applied for the state-of-charge optimization of PHEVs. In this research, hybrid PSOGSA has performed very well in producing better results than other stand-alone optimization techniques.

     

Structure-property relationships in isotactic poly(propylene)/ethylene propylene rubber/montmorillonite nanocomposites

Nanocomposites based on isotactic polypropylene/ethylene propylene rubber (iPP/EPR) were prepared adding different amounts of montmorillonite and maleated polypropylene. The structure and morphology of the samples were characterized by small angle X-ray scattering, wide angle X-ray diffraction, electronic and optical microscopy and differential scanning calorimetry, iPP showed a polymorphic behavior. Clay disrupted the ordered crystallization of iPP and had a key role in shaping the distribution of iPP and EPR phases: larger filler contents brought about smaller, less coalesced and more homogeneous rubber domains. Clay distributed itself only in the continuous phase and not in the rubber domains. Tactoids persisted on the surface of the sample, while delamination proceeded to a greater degree in the bulk of the materials. Melt flow rate, impact strength, flexural and tensile properties, were also measured and a structure-property correlation was sought. Clay produced its most significant effect on physical-mechanical properties by controlling the size of rubber domains in the heterophasic matrix. This allowed to obtain nanocomposites with increased stiffness and impact strength, a remarkable achievement for polymer layered-silica nanocomposites that usually suffer the drawback of being stiffer than the unfilled matrix, but at the same time with a lower resistance to impact. A beneficial effect of clay on thermal stability was also observed.     

Dilatometric behavior and microstructure of sintered Fe–NbC and Fe–TaC composites

Fe-reinforced composites were manufactured by the addition of 10–20 wt.% NbC or TaC particles aiming at improved mechanical and wear behavior. Two varieties of Fe powders from Hoeganaes Corp. were used, Ancorsteel 1000B and 45P. Composites produced using the former variety included a small amount of Fe₃P to induce liquid-phase sintering whereas 45P powder was pre-alloyed with P by the manufacturer. The hardness of the matrix was adjusted adding carbon to the composite mixture. The powders were milled for different times and annealed prior to pressing. A dilatometric study was carried out under hydrogen to establish optimum sintering profiles. Relative densities up to 97% TD were achieved. Both microstructure and density of the sintered pellets were evaluated in order to establish correlations involving composition, processing parameters and microstructure of the composite.     

Chemometric study of Maya Blue from the voltammetry of microparticles approach

The use of the voltammetry of microparticles at paraffin-impregnated graphite electrodes allows for the characterization of different types of Maya Blue (MB) used in wall paintings from different archaeological sites of Campeche and YucatAn (Mexico). Using voltammetric signals for electron-transfer processes involving palygorskite-associated indigo and quinone functionalities generated by scratching the graphite surface, voltammograms provide information on the composition and texture of MB samples. Application of hierarchical cluster analysis and other chemometric methods allows us to characterize samples from different archaeological sites and to distinguish between samples proceeding from different chronological periods. Comparison between microscopic, spectroscopic, and electrochemical examination of genuine MB samples and synthetic specimens indicated that the preparation procedure of the pigment evolved in time via successive steps anticipating modern synthetic procedures, namely, hybrid organic-inorganic synthesis, temperature control of chemical reactivity, and template-like synthesis.     

Renormalized Impact Factor

Many aspects determine the quality of scientific journals. The impact factor is one of these quantitative parameters. However, the impact factor has a strong dependence on the journal discipline. This dependence forbids a direct comparison between different journals without introducing external considerations. In this paper, a renormalized impact factor, F_r, inspired in the definition of dimensionless physical parameters, is proposed. F_r allows a direct comparison among journals classified into different categories and, furthermore, the time evolution analysis of the journal's role in its field.     

Abnormal suppression of 3-hydroxy-3-methylglutaryl-CoA reductase activity in cultured human fibroblasts by hypertriglyceridemic very low density lipoprotein subclasses

Our previous studies showed that hypertriglyceridemic very low density lipoproteins (HTG VLDL) are functionally abnormal. HTG VLDL, but not normal VLDL, suppress HMG-CoA reductase in cultured normal human fibroblasts. To determine if the suppression by HTG VLDL resulted from a subpopulation of smaller suppressive particles, more homogeneous subclasses of VLDL-VLDL₁ (S_f 100–400), VLDL₂ (S_f 60–100), and VLDL₃ (S_f 20–60) were obtained from the d<1.006 (g°ml⁻¹) fraction of normal and hypertriglyceridemic plasma by flotation through a discontinuous salt gradient and tested for suppression in normal human fibroblasts. VLDL₁ and VLDL₂ from each of the 12 normolipemic subjects tested failed to suppress HMG-CoA reductase activity in normal fibroblasts. Eleven out of 12 preparations of normal VLDL₃ suppressed HMG-CoA reductase, but only one-third as effectively as LDL. By contrast, the VLDL₁, VLDL₂ and VLDL₃ from 15 out of 17 hypertriglyceridemic patients (hyperlipoproteinemia Types IIb, III, IV and V) were highly effective in suppression, with half-maximal suppression at 0.1–2.0 μg VLDL protein/ml. The VLDL abnormality is apparently associated with hypertriglyceridemia and not hypercholesterolemia, since VLDL from a homozygous familial hypercholesterolemia patient with a Type IIa pattern did not suppress whereas each of the VLDL subclasses from a Type IIb patient suppressed. Suppression by HTG VLDL in normal cells is apparently a consequence of interaction of the protein portion of the VLDL with the specific LDL cell surface receptor since HTG VLDL₁ treated with 0.1 M 1,2-cyclohexanedione to block arginyl residues failed to suppress the enzyme. Moreover, hypertriglyceridemic S_f 60–400 VLDL failed to suppress HMG-CoA reductase activity in LDL receptor-negative fibroblasts. There were no consistent major compositional differences between comparable normal and hypertriglyceridemic VLDL subclasses which could account for differences in suppression. All VLDL subclasses from Type III subjects were enriched in cholesteryl esters and depleted in triglyceride, relative to the corresponding normal VLDL subclasses. However, Type IV and Type V VLDL subclasses were normal in this repect. We conclude from these studies that small particle diameter is not required for suppression, since HTG VLDL₁ and VLDL₂ which contained few, if any, small particles were effective in suppression. Presented as part of the symposium “Low Density and Very Low Density Lipoproteins” at the American Oil Chemists' Society meeting on May 2, 1979, in San Francisco.     

I-Competere: Using applied intelligence in search of competency gaps in software project managers

People in software development teams are crucial in order to gain and retain strategic advantage inside a highly competitive market. As a result, human factors have gained attention in the software industry. Software Project Managers are decisive to achieve project success. A competent project manager is capable of solving any problem that an organization may encounter, regardless of its complexity. This paper presents I-Competere which is a tool developed to forecast competence gaps in key management personnel by predicting planning and scheduling competence levels. Based on applied intelligence techniques, I-Competere allows the forecast and anticipation of competence needs thus articulating personnel development tools and techniques. The results of the test, using several artificial neural networks, are more than promising and show prediction accuracy.