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Qualitative Explanation (qualitative + explanation)
Selected AbstractsGranular mixing and segregation in a horizontal rotating drum: A simulation study on the impact of rotational speed and fill levelAICHE JOURNAL, Issue 12 2008M. M. H. D. Arntz Abstract The rich phase behavior of granular beds of bidisperse hard spherical particles in a rotating horizontal drum is studied by Discrete Element Method (DEM) simulations. Several flow regimes and various forms of radial segregation, as well as mixing, are observed by systematically varying the operational parameters of the drum, i.e. fill level and angular velocity, over a wide range. Steady states after several dozen revolutions are summarized in two bed behavior diagrams, showing strong correlations between flow regime and segregation pattern. An entropy method quantifies the overall degree of mixing, while density and velocity plots are used to analyze the local properties of the granular bed. The percolation mechanism may provide a qualitative explanation for the distinct segregation processes, and for the transient mixing in nonradially segregated beds. Initially blockwise segregated beds are found to mix before radial segregation sets in. High fill fractions (>65%) show the most intense segregation. © 2008 American Institute of Chemical Engineers AIChE J, 2008 [source] Bandwidth limitation of two-port fed and self-phased quadrifilar helix antennasMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 1 2005M. Amin Abstract The bandwidth of a resonant quadrifilar helix antenna (QHA) is shown to be strongly dependent on the design of the feed network. In this paper, we compare the impedance and radiation-pattern performance of two QHAs driven by different feed arrangements. A qualitative explanation for the difference in the behaviour of the antenna is given by observing the amplitude and phase distribution of the current in the helices. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 11,15, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20886 [source] Comparing factor analytical and circumplex models of brand personality in brand positioningPSYCHOLOGY & MARKETING, Issue 10 2009Jia Yao Esther Bao Competition has never been greater, which means it is more important than ever that organizations assess their brand management strategies, including brand personality management. However, little empirical research addresses the brand personality concept, particularly its role in product evaluation. An exception, which views brand personality as a set of human personality characteristics associated with a brand, has been criticized for its use of a factor analytical approach. An alternative approach posits that the brand represents a relationship partner with which the consumer may choose to engage; it corresponds to the interpersonal circumplex approach to personality modeling. The present study compares these two approaches by developing brand positioning maps and predicting consumer outcomes. The results support the factor approach in a purely quantitative sense, but the circumplex approach offers both a richer qualitative explanation of the findings by encompassing a broad spectrum of traits and a more diagnostic prediction of consumer outcomes. The alternative conceptualization of brand personality contained in these results should be of interest to brand managers. © 2009 Wiley Periodicals, Inc. [source] The combination of molecular dynamics with crystallography for elucidating protein,ligand interactions: a case study involving peanut lectin complexes with T-antigen and lactoseACTA CRYSTALLOGRAPHICA SECTION D, Issue 11 2001J. V. Pratap Peanut lectin binds T-antigen [Gal,(1,3)GalNAc] with an order of magnitude higher affinity than it binds the disaccharide lactose. The crystal structures of the two complexes indicate that the higher affinity for T-antigen is generated by two water bridges involving the acetamido group. Fresh calorimetric measurements on the two complexes have been carried out in the temperature range 280,313,K. Four sets of nanosecond molecular-dynamics (MD) simulations, two at 293,K and the other two at 313,K, were performed on each of the two complexes. At each temperature, two somewhat different protocols were used to hydrate the complex in the two runs. Two MD runs under slightly different conditions for each complex served to assess the reliability of the approach for exploring protein,ligand interactions. Enthalpies based on static calculations and on MD simulations favour complexation involving T-antigen. The simulations also brought to light ensembles of direct and water-mediated protein,sugar interactions in both the cases. These ensembles provide a qualitative explanation for the temperature dependence of the thermodynamic parameters of peanut lectin,T-antigen interaction and for the results of one of the two mutational studies on the lectin. They also support the earlier conclusion that the increased affinity of peanut lectin for T-antigen compared with that for lactose is primarily caused by additional water bridges involving the acetamido group. The calculations provide a rationale for the observed sugar-binding affinity of one of the two available mutants. Detailed examination of the calculations point to the need for exercising caution in interpreting results of MD simulations: while long simulations are not possible owing to computational reasons, it is desirable to carry out several short simulations with somewhat different initial conditions. [source] | ||||||||||