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Step-by-step Procedure (step-by-step + procedure)
Selected AbstractsQuality modeling and analysis of polymer composite productsPOLYMER COMPOSITES, Issue 4 2006R.T. Durai Prabhakaran The present article gives a new direction for quality modeling and analysis of polymer matrix composite products. Quality of composite products depends upon conformance of requirements of the customer. These requirements are translated into design specifications of all the contributing factors and subsystems up to component level of composite system. Quality of interaction amongst different subsystems, sub-subsystems, and other factors affects quality of products are also to be considered. Therefore, the present article considers quality of subsystems as well as quality of all interactions together and modeled using graph theory, matrix algebra as quality graph, quality matrix, and quality permanent function of the composite product. These models are useful to design quality of every subsystem and factors in such a manner that can lead to achieve six-sigma limits (almost zero error) i.e. 3.34 defects per million products produced. A number of analytical tests derived from these models help to carry out optimum selection of qualities of subsystems and interactions for designing competitive composite products. SWOT (strength,weakness,opportunities,threats) analysis integrated with these models becomes very powerful tool to convert an unsuccessful product into successful competitive product. Evaluation, ranking, and comparison procedures can be developed with the help of these proposed models. Coefficients of similarity and dissimilarity are developed for comparison among feasible products. Step-by-Step procedure based on systems approach is useful to designer, manufacturer at conceptual stage of design, and during manufacturing stages of composite products. This is basically a virtual prototyping methodology of complete system, leading to high quality competitive composite products. POLYM. COMPOS. 27:329,340, 2006. © 2006 Society of Plastics Engineers [source] Introduction to diffusion tensor imaging mathematics: Part III.CONCEPTS IN MAGNETIC RESONANCE, Issue 2 2006Tensor calculation, noise, optimization, simulations Abstract The mathematical aspects of diffusion tensor magnetic resonance imaging (DTMRI, or DTI), the measurement of the diffusion tensor by magnetic resonance imaging (MRI), are discussed in this three-part series. Part III begins with a comparison of different ways to calculate the tensor from diffusion-weighted imaging data. Next, the effects of noise on signal intensities and diffusion tensor measurements are discussed. In MRI signal intensities as well as DTI parameters, noise can introduce a bias (systematic deviation) as well as scatter (random deviation) in the data. Propagation-of-error formulas are explained with examples. Step-by-step procedures for simulating diffusion tensor measurements are presented. Finally, methods for selecting the optimal b factor and number of b = 0 images for measuring several properties of the diffusion tensor, including the trace (or mean diffusivity) and anisotropy, are presented. © 2006 Wiley Periodicals, Inc. Concepts Magn Reson Part A 28A: 155,179, 2006 [source] Molecular Tailored Histidine-Based Complexing Surfactants: From Micelles to HydrogelsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 23 2009Patrick Gizzi Abstract Novel histidine-based complexing surfactants, designed as AA-His-EOm -Cn, containing trifunctional moduli (peptidic/hydrophilic/hydrophobic) were synthesized by a modular step-by-step procedure, which allowed easy structural changes, and consequently correlations between their molecular structures and their self-assembling properties could be established. Thus, micelles or hydrogels could be obtained by simply modifying the hydrophobic tail lengths or the junction between the different moduli of the designed compounds. At low pH values, all compounds were surface active in aqueous solutions. At higher pH values, in the range 8,10, micellization took place for decyl compounds (n = 10), whereas hydrogelation occurred for longer chain lengths (n = 12, 14), and this, at very-low concentrations of surfactant (<0.3 wt.-%), could thus act as low molecular weight gelator (LMWG). The driving forces for gel formation were noncovalent intermolecular interactions such as ,-stacking and hydrophobic and hydrogen-bonding interactions.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] A step-by-step application of Sandia method in developing typical meteorological years for different locations in OmanINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 8 2005Naseem M. Sawaqed Abstract This paper reports on the development of typical meteorological years (TMYs) for seven different locations in Oman based on measured meteorological data. Depending on the availability of data the TMYs developed using Sandia method used data covering 7,17 years. The method as implemented here in a step-by-step procedure with illustrations is made simple. The procedure described herein is computerized and can handle any number of data sets in an easy-to-use manner. This should facilitate the development of TMYs for any location where enough data is available. Sensitivity analysis of different weights assigned to different weather parameters shows that Sandia method is highly affected by solar flux even if its weight is reduced by half while the weights of other parameters such as temperature, wind, and relative humidity have less impact on the selection of TMY. Copyright © 2005 John Wiley & Sons, Ltd. [source] Shaping stable periodic motions of inertia wheel pendulum: theory and experiment,ASIAN JOURNAL OF CONTROL, Issue 5 2009Leonid B. Freidovich Abstract We consider an underactuated two-link robot called the inertia wheel pendulum. The system consists of a free planar rotational pendulum and a symmetric disk attached to its end, which is directly controlled by a DC-motor. The goal is to create stable oscillations of the pendulum, which is not directly actuated. We exploit a recently proposed feedback-control design strategy based on motion planning via virtual holonomic constraints. This strategy is shown to be useful for design of regulators for achieving orbitally exponentially stable oscillatory motions. The main contribution is a step-by-step procedure on how to achieve oscillations with pre-specified amplitude from a given range and an arbitrary independently chosen period. The theoretical results are verified via experiments with a real hardware setup. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] Intramolecular Energy Transfer in Pyrene,Bodipy Molecular Dyads and TriadsCHEMISTRY - A EUROPEAN JOURNAL, Issue 24 2005Raymond Ziessel Dr. Abstract Molecules bearing a 4,4-difluoro-8-(aryl)-1,3,5,7-tetramethyl-2,6-diethyl-4-bora-3a,4a-diaza- s -indacene (bodipy) core and 1-pyrenyl-1-phenyl-4-(1-ethynylpyrene), or 1-phenyl-4-[1-ethynyl-(6-ethynylpyrene)pyrene] units were constructed in a step-by-step procedure based on palladium(0)-promoted cross-coupling reactions with the required preconstructed modules. X-ray structures of single crystals reveal a twisted arrangement of the two chromophores. In one case, an almost perfect orthogonal arrangement is found. These dyes are strongly luminescent in solution and display rich electrochemistry in which all redox processes of the bodipy and pyrene fragments are clearly resolved. The absorption spectra indicate that the bodipy and pyrene chromophores are spectrally isolated, thereby inducing a large "virtual" Stokes shift. The latter is realised by efficient transfer of intramolecular excitation energy by the Förster dipole,dipole mechanism. The rate of energy transfer depends on the structure of the dual-dye system and decreases as the centre-to-centre separation increases. The energy transfer efficiency, however, exceeds 90,% in all cases. The linkage of two pyrene residues by an ethyne group leads to a decrease in the energy-transfer efficiency, with the two polycycles acting as a single chromophore. The directly linked bodipy,pyrene dual dye binds to DNA and operates as an efficient solar concentrator when dispersed in plastic. De nouvelles molécules comprenant un c,ur 4,4-difluoro-8-(aryl)-1,3,5,7-tetramethyl-2,6-diethyl-4-bora-3a,4a-diaza-s-indacene (appelé bodipy) et des fragments 1-pyrènyl, 1-phényl-4-(1-éthynylpyrène), ou 1-phényl-4-[1-éthynyl-(6-éthynylpyrène)pyrène] ont été synthétisées par le biais de couplage croisés entre des modules pré-construits. Ces réactions ont été catalysées par du palladium sous-ligandé dans des conditions anaérobiques. Dans deux cas typiques la structure moléculaire déterminée par diffraction aux rayons X sur monocristal révèle un arrangement quasi perpendiculaire des deux sous-unités bodipy et pyrène. L'ensemble des composés sont très fluorescents en solution et dévoilent une voltammétrie cyclique riche en signaux réversibles. L'ensemble des processus d'oxydation et de réduction localisés sur les sous-unité pyrène et bodipy sont bien résolus. De plus ces deux fragments sont spectroscopiquement différenciées ce qui permet d'obtenir des déplacements de Stokes important lorsque la partie pyrène est excitée et que la fluorescence de la partie bodipy est observée. Le processus responsable de ce phénomène est un transfert d'énergie ayant lieu par résonance (mécanisme dit de Förster par interaction dipôle-dipôle). La vitesse de ce transfert d'énergie dépends de la structure moléculaire et décroît en augmentant la distance ente les deux chromophores. L'efficacité de ce transfert est supérieur à 90,% dans l'ensemble des cas étudiés. Cependant la connexion par une liaison triple des motifs bodipy et pyrène diminue l'efficacité de ce transfert. La molécule comportant un pyrène directement connecté au bodipy se lie fortement à l'ADN et se comporte comme un concentrateur de photons lorsque dispersé dans des plastiques rigides. [source] Robust design of communication systems: The case of expedited forwarding of voice traffic in differentiated services networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 10 2007Hyoup-Sang Yoon Abstract Design of experiments (DOE) is gaining acceptance in the community of telecommunication researchers, especially during the past several years. In this paper, a state-of-the-art review on the use of DOE in the field of communication networks is presented, and the need for introducing a systematic robust design methodology to network simulations or testbed experiments is identified in ensuring robust behaviours of a network against uncontrollable sources of variation. Then, the Taguchi robust design methodology is applied for optimizing the expedited forwarding (EF) of voice traffic in a differentiated services network, and its step-by-step procedures are described in detail. The experimental data are collected using the ns-2 simulator, and the SN ratio, a robustness measure, is analysed to determine an optimal design condition for each performance characteristic. The analysis results show that ,type of queue scheduling schemes' is a major control factor for ensuring robust behaviours of one-way delay and jitter while ,EF queue size' is for throughput and loss rate. Finally, a compromised optimal design condition is identified using a desirability function approach adapted to multi-characteristic robust design problems. Copyright © 2007 John Wiley & Sons, Ltd. [source] Data linkage using probabilistic decision rules: A primer,BIRTH DEFECTS RESEARCH, Issue 11 2008Craig Alan Mason Abstract Electronic data linkage is increasingly being used by researchers and health professionals in the birth defects field as a tool for enhancing both research and service/care. However, in many cases, a common pre-existing ID number does not exist across different datasets, and common identifiers, such as names or dates of birth, which could be used to match records, may be known to contain errors or even legitimate differences over time. In such situations, probabilistic matching, which does not require that all identifying fields exactly agree in order for one to conclude that two records belong to the same individual, can be a valuable tool for improving data linkage. However, probabilistic matching is computationally complex and demanding, and not well understood by many who may wish to apply it in their work. Therefore, the purpose of this article is to provide an overview of one approach to probabilistic matching, including the step-by-step procedures involved in the calculation of indices corresponding to the likelihood that two records are a correct match. In addition, the use of multiple iterative protocols, in which several different matching strategies are used in order to maximize the number of linked records, is discussed. Finally, issues related to deduplication and verification of internal-consistency in the linked data set are also reviewed. Birth Defects Research (Part A), 2008. © 2008 Wiley-Liss, Inc. [source] New approach for rapid detection of known hemoglobin variants using LC-MS/MS combined with a peptide database,JOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 3 2007F. Basilico Abstract The identification of hemoglobin (Hb) variants is usually performed by means of different analytical steps and methodologies. Phenotypic methods, such as gel electrophoresis and high performance liquid chromatography, are used to detect the different electrophoretic or chromatographic behaviors of hemoglobin variants in comparison to HbA0 used as a control. These data often need to be combined with mass spectrometry analyses of intact globins and their tryptic peptide mixtures. As an alternative to a ,step-by-step' procedure, we have developed a ,single step' approach for the identification of Hb variants present in biological samples. This is based on the µHPLC-ESI-MS/MS analysis of the peptide mixture generated by a tryptic digestion of diluted Hb samples and an in-house new database containing solely the variant tryptic peptide of known human Hb variants. The experimental results (full MS and MS/MS spectra) are correlated with theoretical mass spectra generated from our in-house-built variant peptide database (Hbp) using the SEQUEST algorithm. Simple preparation of samples and an automated identification of the variant peptide are the main characteristics of this approach, making it an attractive method for the detection of Hb variants at the routine clinical level. We have analyzed 16 different samples, each containing a different known variant of hemoglobin. Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||