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Factor Method (factor + method)
Selected AbstractsDesign of a composite beam using the failure probability-safety factor methodINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 9 2005E. Castillo Abstract The paper shows the practical importance of the failure probability-safety factor method for designing engineering works. The method provides an automatic design tool by optimizing an objective function subject to the standard geometric and code constraints, and two more sets of constraints, that guarantee some given safety factors and failure probability bounds, associated with a given set of failure modes. Since a direct solution of the optimization problem is not possible, the method proceeds as a sequence of three steps: (a) an optimal classical design, based on given safety factors, is done, (b) failure probabilities or bounds of all failure modes are calculated, and (c) safety factors bounds are adjusted. This implies a double safety check that leads to safer structures and designs less prone to wrong or unrealistic probability assumptions, and to excessively small (unsafe) or large (costly) safety factors. Finally, the actual global or combined probabilities of the different failure modes and their correlation are calculated using a Monte Carlo simulation. In addition, a sensitivity analysis is performed. To this end, the optimization problems are transformed into another equivalent ones, in which the data parameters are converted into artificial variables. In this way, some variables of the dual associated problems become the desired sensitivities. The method is illustrated by its application to the design of a composite beam. Copyright 2004 © John Wiley & Sons, Ltd. [source] Recognition versus Disclosure: An Investigation of the Impact on Equity Risk Using UK Operating Lease DisclosuresJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 9-10 2000Vivien Beattie This study examines the equivalency of accounting recognition versus disclosure. OLS regression analysis is used to determine whether there is an association between equity risk and an adjustment to financial risk for off-balance sheet operating leases. Two methods of adjustment are considered: constructive capitalisation and a simple factor method. The observation of a reliably positive association suggests that UK investors/analysts view operating leases from a property rights perspective rather than an ownership perspective. This supports the argument for recognition of all lease rights and obligations ,on-balance sheet', as proposed in the recent G4+1 discussion paper ASB (1999). [source] A Qualitative and Quantitative Approach to Determine the Optimum Combination of Feeding Stimulants for Striped Bass Morone saxatilis Using an Agar Gel CarrierJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2002Elias Papatryphon A series of experiments was conducted to determine the optimum combination of previously identified feeding stimulants (FS), namely L-alanine (Ala), L-serine (Ser), inosine-5,-monophosphate (IMP), and betaine (Bet), for striped bass Morone saxatilis. Three experiments were conducted to determine the optimum combination of FS using an agar gel matrix as a carrier. In the first experiment a 24 factorial experiment was conducted to test all possible combinations of the four FS at two levels, 0 and 0.1 M. Significant interactions between the FS were found, suggesting the complexity of gustatory stimulation and palatability. In the second experiment a 4 × 6 factorial design was employed to test each FS alone and at concentrations ranging from 0 to 8% in order to determine the minimum level at which maximal stimulation is achieved. The results suggest that there is no significant improvement in feed intake beyond the 1 % level of supplementation for all the FS. In addition, Ala produced a significantly greater response compared to all other FS. In the last experiment, a modified single factor method was used to estimate the optimum levels for each FS in a mixture. The range of the concentrations tested was 0,1% of the agar gel for each FS. Combining all four compounds yielded maximal stimulation. The levels of each compound in the final optimum combination of FS were: Ala, 0.4; Ser, 0.6; Bet, 0.4; and IMP, 0.3% of the agar gel. [source] Modulation bandwidth of semiconductor lasers based on coupled quantum wellsMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2004M. S. Wartak Abstract The effect of well coupling on differential gain and maximum-modulation bandwidth for semiconductor lasers based on coupled quantum wells is analyzed using the K -factor method. We determine differential gain in coupled quantum wells within the self-consistent solution of the Poisson, Schroedinger, and 4 × 4 Luttinger,Kohn equations. The multiple-body effects of bandgap renormalization, coulombic scattering interactions, and a nonMarkovian distribution are also included. The analysis has been performed for coupled wells at 1.55 ,m in an InGaAsP/InP lattice-matched system grown in the [001] direction. Our results suggest that in order to maximize modulation bandwidth and differential gain, one should design structures with barrier widths larger than 40 Å. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 272,274, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20275 [source] Investigation of Drying Geldart D and B Particles in Different Fluidization RegimesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 6 2006Wai Kiong Ng Abstract Drying of nylon (Geldart D) and expanded polystyrene (Geldart B) particles in fixed and fluidized beds were studied experimentally and theoretically. Fluidized bed dryers are sometimes operated at velocities beyond bubbling fluidization to mitigate against de-fluidization of surface wet particles. It was found that theoretical analysis using three different drying methods could predict the constant-drying rate at such velocities and also across the entire fluidization regimes (fixed bed, bubbling, slugging and turbulent fluidization) as long as the bed remains completely fluidized. Results also showed that the theoretical predictions were accurate beyond previously reported velocity limits in a laboratory scale dryer. During bubbling fluidization, the cross flow factor method was used effectively to predict the influence of bubble phase on drying rates. In the falling-rate period, it is demonstrated that the drying behaviour of nylon at different gas velocities can be characterised by a single normalized drying curve. On a étudié de manière expérimentale et théorique le séchage de particules de nylon (Geldart D) et de polystyrène expansé (Geldart B) dans des lits fixes et fluidisés. Les séchoirs à lits fluidisés fonctionnent parfois à des vitesses qui vont au-delà de la fluidisation bullante pour atténuer la dé-fluidisation des particules mouillées en surface. On a trouvé que l'analyse théorique à l'aide de trois méthodes de séchage différentes pouvait prédire le taux de séchage constant à de telles vitesses et également dans tous les régimes de fluidisation (fluidisation à lit fixe, bullante, pistonnante et turbulente) tant que le lit demeure entièrement fluidisé. Les résultats montrent également que les prédictions théoriques sont précises au-delà des limites de vitesse mentionnées précédemment dans un séchoir à l'échelle de laboratoire. Lors de la fluidisation bullante, on a utilisé avec efficacité la méthode du facteur d'écoulement transversal afin de prédire l'influence de la phase bullante sur les vitesses de séchage. Dans la période de vitesse descendante, on démontre que le comportement de séchage du nylon à différentes vitesses de gaz peut être caractérisé par une courbe de séchage normalisée unique. [source] | ||||||||||