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Analytical Approach (analytical + approach)
Kinds of Analytical Approach Selected AbstractsTHE ,LORDS OF THE RINGS': AN ANALYTICAL APPROACH TO THE RIDDLE OF THE ,KNOSSIAN REPLICA RINGS'BULLETIN OF THE INSTITUTE OF CLASSICAL STUDIES, Issue 1 2009YUVAL GOREN No abstract is available for this article. [source] An Extended Analytical Approach to Credit Risk ManagementECONOMIC NOTES, Issue 2 2002Alexandre Kurth Among the ,reduced form models' for measuring the credit risk of a bank's portfolio is CreditRisk+, which provides a closed,form solution for calculating the portfolio loss distribution based on an actuarial approach. The limitations of this model are well known, but they are often misinterpreted as being deeply embedded within the model. Dismantling the mathematical components of the model allows one to modify and extend it in several ways while remaining within an analytical approach. One of the most unattractive features is the orthogonality of the background factors or sectors as it hinders any resemblance to real,world macroeconomic indexes or industrial sectors and geographical areas. Among other extensions, which we mention briefly, we present in more detail how the original model can be amended to consider correlations among default risk sectors and among severity risk segments. These extensions are applied to real,life data, based on mortality rate data produced by the Italian Central Bank. (J.E.L.: C00, C51). [source] Analytical approach for the toroidal relaxation of viscoelastic earthGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2006Hansheng Wang SUMMARY This paper is concerned with post-seismic toroidal deformation in a spherically symmetric, non-rotating, linear-viscoelastic, isotropic Maxwell earth model. Analytical expressions for characteristic relaxation times and relaxation strengths are found for viscoelastic toroidal deformation, associated with surface tangential stress, when there are two to five layers between the core,mantle boundary and Earth's surface. The multilayered models can include lithosphere, asthenosphere, upper and lower mantles and even low-viscosity ductile layer in the lithosphere. The analytical approach is self-consistent in that the Heaviside isostatic solution agrees with fluid limit. The analytical solution can be used for high-precision simulation of the toroidal relaxation in five-layer earths and the results can also be considered as a benchmark for numerical methods. Analytical solution gives only stable decaying modes,unstable mode, conjugate complex mode and modes of relevant poles with orders larger than 1, are all excluded, and the total number of modes is found to be just the number of viscoelastic layers between the core,mantle boundary and Earth's surface,however, any elastic layer between two viscoelastic layers is also counted. This confirms previous finding where numerical method (i.e. propagator matrix method) is used. We have studied the relaxation times of a lot of models and found the propagator matrix method to agree very well with those from analytical results. In addition, the asthenosphere and lithospheric ductile layer are found to have large effects on the amplitude of post-seismic deformation. This also confirms the findings of previous works. [source] Analytical approach with Laplace transform to the inverse problem of one-dimensional heat conduction transfer: Application to second and third boundary conditionsHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 1 2003Masanori Monde Abstract An analytical method using Laplace transformation has been developed for one-dimensional heat conduction. This method succeeded in explicitly deriving the analytical solution by which the surface temperature for the first kind of boundary condition can be well predicted. The analytical solutions for the surface temperature and heat flux are applied to the second and third of the boundary conditions. These solutions are also found to estimate the corresponding surface conditions with a high degree of accuracy when the surface conditions smoothly change. On the other hand, when these conditions erratically change such as the first derivative of temperature with time, the accuracy of the estimation becomes slightly less than that for a smooth condition. This trend in the estimation is similar irrespective of any kind of boundary condition. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(1): 29,41, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10069 [source] Analytical approach to the optimal adaptation rate of reconfigurable radio networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2008R. Fraile Abstract Flexible radio resource management schemes are nowadays used within a wide range of systems. However, the optimal selection for their adaptation rate is still an open research issue. This paper presents an analytical approach to such problem, which consists in a combined analysis of the dynamics of the session-arrival process and the estimation of the mean traffic load from network measurements. From this study, it is concluded that both aspects pose an upper limit on the optimal system adaptation rate, being the most restrictive the one depending on the mean traffic load estimation. A specific procedure for deriving such limit on adaptation rate is provided. It is shown that the derived value directly depends on the mean service duration. The application of the whole analysis is illustrated with an example based on a set of measurements from a live network. Copyright © 2008 John Wiley & Sons, Ltd. [source] Metacommunity patterns of highly diverse stream midges: gradients, chequerboards, and nestedness, or is there only randomness?ECOLOGICAL ENTOMOLOGY, Issue 5 2005Jani Heino Abstract., 1.,Several non-random patterns in the distribution of species have been observed, including Clementsian gradients, Gleasonian gradients, nestedness, chequerboards, and evenly spaced gradients. Few studies have examined these patterns simultaneously, although they have often been studied in isolation and contrasted with random distribution of species across sites. 2.,This study examined whether assemblages of chironomid midges exhibit any of the idealised distribution patterns as opposed to random distribution of species across sites within the metacommunity context in a boreal drainage system. Analyses were based on stream surveys conducted during three consecutive years. Analytical approaches included ordinations, cluster analysis, null models, and associated randomisation methods. 3.,Midge assemblages did not conform to Clementsian gradients, which was evidenced by the absence of clearly definable assemblage types with numerous species exclusive to each assemblage type. Rather, there were signs of continuous Gleasonian variability of assemblage composition, as well as significant nested subset patterns of species distribution. 4.,Midge assemblages showed only weak relationships with any of the measured environmental variables, and even these weak environmental relationships varied among years. 5.,Midge assemblages did not appear to be structured by competition. This finding was somewhat problematic, however, because the two indices measuring co-occurrence provided rather different signs of distribution patterns. This was probably a consequence of how they actually measure co-occurrence. 6.,Although midge assemblages did not show a perfect match with any of the idealised distribution patterns, they nevertheless showed a resemblance to the empirical patterns found previously for several plant and animal groups. [source] Analytical approaches for transplant research, 2004AMERICAN JOURNAL OF TRANSPLANTATION, Issue 4p2 2005Douglas E. Schaubel This article provides detailed explanations of the methods frequently employed in outcomes analyses performed by the Scientific Registry of Transplant Recipients (SRTR). All aspects of the analytical process are discussed, including cohort selection, post-transplant follow-up analysis, outcome definition, ascertainment of events, censoring, and adjustments. The methods employed for descriptive analyses are described, such as unadjusted mortality rates and survival probabilities, and the estimation of covariant effects through regression modeling. A section on transplant waiting time focuses on the kidney and liver waiting lists, pointing out the different considerations each list requires and the larger questions that such analyses raise. Additionally, this article describes specialized modeling strategies recently designed by the SRTR and aimed at specific organ allocation issues. The article concludes with a description of simulated allocation modeling (SAM), which has been developed by the SRTR for three organ systems: liver, thoracic organs, and kidney-pancreas. SAMs are particularly useful for comparing outcomes for proposed national allocation policies. The use of SAMs has already helped in the development and implementation of a new policy for liver candidates with high MELD scores to be offered organs regionally before the organs are offered to candidates with low MELD scores locally. [source] Analytical approaches for transplant researchAMERICAN JOURNAL OF TRANSPLANTATION, Issue 2003Robert A. Wolfe First page of article [source] Temperate marine reserves: global ecological effects and guidelines for future networksCONSERVATION LETTERS, Issue 6 2009Gavin B. Stewart Abstract Marine reserves, areas closed to all fishing and other extractive activities, provide a refuge for species of commercial and conservation importance. Given the considerable resources committed to designing temperate reserve networks, we synthesized data from temperate reserves worldwide to determine their ecological effects. In common with other studies, we found higher density, biomass, and species richness in temperate marine reserves compared to adjacent exploited areas. However, there was considerable heterogeneity in magnitude of effect among reserves, variability which was largely unexplained by species or reserve characteristics. Our analytical approach allowed for formal power analyses, indicating that detection of large reserve effects in temperate systems globally requires monitoring at least 37 reserves. These results must be qualified by the limitations of data available and will undoubtedly vary at different spatio-temporal scales and for different focal species, but provide guidance for the design and monitoring of future marine conservations plans. International commitments toward establishment of multiple reserves offer a unique opportunity to assess reserve effectiveness; this opportunity can only be realized if reserves are designed to achieve clear and quantifiable objectives and are adequately monitored before and after establishment, based on appropriate power analyses, to assess how well those objectives are achieved. [source] Advantages of mixed effects models over traditional ANOVA models in developmental studies: A worked example in a mouse model of fetal alcohol syndromeDEVELOPMENTAL PSYCHOBIOLOGY, Issue 7 2007Patricia E. Wainwright Abstract Developmental studies in animals often violate the assumption of statistical independence of observations due to the hierarchical nature of the data (i.e., pups cluster by litter, correlation of individual observations over time). Mixed effect modeling (MEM) provides a robust analytical approach for addressing problems associated with hierarchical data. This article compares the application of MEM to traditional ANOVA models within the context of a developmental study of prenatal ethanol exposure in mice. The results of the MEM analyses supported the ANOVA results in showing that a large proportion of the variability in both behavioral score and brain weight could be explained by ethanol. The MEM also identified that there were significant interactions between ethanol and litter size in relation to behavioral scores and brain weight. In addition, the longitudinal modeling approach using linear MEM allowed us to model for flexible weight gain over time, as well as to provide precise estimates of these effects, which would be difficult in repeated measures ANOVA. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 664,674, 2007. [source] Initial stiffness of reinforced concrete structural walls with irregular openingsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2010Bing Li Abstract Reinforced concrete (RC) structural walls with openings are the primary lateral-load-carrying elements utilized in many structures designed to resist earthquakes. A review of the technical literature shows that there is a considerable amount of uncertainty with regards to the elastic stiffness of these structures when subjected to seismic excitations. Current design practices often employ a stiffness reduction factor to deal with this uncertainty. In an attempt to develop additional information regarding the stiffness of these structures, this paper discusses an approach to determine the initial stiffness of RC structural walls with irregular openings and low aspect ratios. This approach would consider the effect of both flexural and shear deformations. As a part of this study, an analytical approach to determine stiffness was also developed and validated by comparing theoretical and experimental results obtained from six RC shear walls with irregular openings. Simple equations for assessing initial stiffness of RC structural walls with irregular openings are then proposed, based on these parametric case studies. Copyright © 2009 John Wiley & Sons, Ltd. [source] A recursive decomposition algorithm for network seismic reliability evaluationEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2002Jie Li Abstract A new probabilistic analytical approach to evaluate seismic system reliability of large lifeline systems is presented in this paper. The algorithm takes the shortest path from the source to the terminal of a node weight or edge weight network as decomposition policy, using the Boolean laws of set operation and probabilistic operation principal, a recursive decomposition process then could be constructed. For a general weight network, the modified Torrieri method (NTR/T method) is introduced to combine with the suggested algorithm. Therefore, the recursive decomposition algorithm may be applied to evaluate the seismic reliability of general lifeline systems. A series of case studies, including a practical district electric power network system and a large urban water supply system, show that the suggested algorithm supplies a useful probabilistic analysis means for the seismic reliability evaluation of large lifeline systems. Copyright © 2002 John Wiley & Sons, Ltd. [source] Setting the absolute tempo of biodiversity dynamicsECOLOGY LETTERS, Issue 7 2007Andrew P. Allen Abstract Neutral biodiversity theory has the potential to contribute to our understanding of how macroevolutionary dynamics influence contemporary biodiversity, but there are issues regarding its dynamical predictions that must first be resolved. Here we address these issues by extending the theory in two ways using a novel analytical approach: (1) we set the absolute tempo of biodiversity dynamics by explicitly incorporating population-level stochasticity in abundance; (2) we allow new species to arise with more than one individual. Setting the absolute tempo yields quantitative predictions on biodiversity dynamics that can be tested using contemporary and fossil data. Allowing incipient-species abundances greater than one individual yields predictions on how these dynamics, and the form of the species-abundance distribution, are affected by multiple speciation modes. We apply this new model to contemporary and fossil data that encompass 30 Myr of macroevolution for planktonic foraminifera. By synthesizing the model with these empirical data, we present evidence that dynamical issues with neutral biodiversity theory may be resolved by incorporating the effects of environmental stochasticity and incipient-species abundance on biodiversity dynamics. [source] Natural Resources and Regional Development: An Assessment of Dependency and Comparative Advantage ParadigmsECONOMIC GEOGRAPHY, Issue 1 2003Thomas Gunton Abstract: The role of natural resources in regional development is the subject of a debate between dependency theorists, who argue that natural resources impede development, and comparative-advantage theorists, who argue that resources can expedite development. This debate is assessed by a case study analysis of the impact of resource development on a regional economy. The case study uses a model to estimate the comparative advantage of the resource sector. The results show that natural resources have the potential to provide a significant comparative advantage relative to other economic sectors by virtue of generating resource rent, which is a surplus above normal returns to other factors of production. The case study also shows that there are considerable risks in resource-led growth, including the propensity to dissipate rent and increase community instability by building surplus capacity. These risks are amenable to mitigation because they are largely the result of poor management of resource development. The case study demonstrates that the most productive analytical approach for understanding the role of natural resources in the development process is a synthetic approach, which combines the insights of the dependency and comparative-advantage paradigms into a unified framework. It also demonstrates that the concept of resource rent, which has frequently been ignored in development theory, must be reintegrated into the unified framework to improve the understanding of the role of natural resources in the regional development process. [source] An Extended Analytical Approach to Credit Risk ManagementECONOMIC NOTES, Issue 2 2002Alexandre Kurth Among the ,reduced form models' for measuring the credit risk of a bank's portfolio is CreditRisk+, which provides a closed,form solution for calculating the portfolio loss distribution based on an actuarial approach. The limitations of this model are well known, but they are often misinterpreted as being deeply embedded within the model. Dismantling the mathematical components of the model allows one to modify and extend it in several ways while remaining within an analytical approach. One of the most unattractive features is the orthogonality of the background factors or sectors as it hinders any resemblance to real,world macroeconomic indexes or industrial sectors and geographical areas. Among other extensions, which we mention briefly, we present in more detail how the original model can be amended to consider correlations among default risk sectors and among severity risk segments. These extensions are applied to real,life data, based on mortality rate data produced by the Italian Central Bank. (J.E.L.: C00, C51). [source] Mass spectrometrical analysis of the mitochondrial carrier Aralar1 from mouse hippocampusELECTROPHORESIS, Issue 11 2010Seok Heo Abstract Aralar1 is a mitochondrial aspartate/glutamate carrier and a key component of the malate,aspartate NADH shuttle system. An analytical approach to obtain high sequence coverage is important to predict conformation, identify splice variants and binding partners or generate specific antibodies. Moreover, a method allowing determination of Aralar1 from brain samples is a prerequisite for evaluating a biological role. Sucrose gradient ultracentrifugation was applied to enrich native membrane protein fractions and these were run on blue-native PAGE, followed by multidimensional gel electrophoresis. Spots from the third-dimensional gel electrophoresis were in-gel digested with trypsin, chymotrypsin and subtilisin. Subsequently, peptides were analyzed by nano-ESI-LC-MS/MS using collision-induced dissociation and electron transfer dissociation modes. ModiroÔ v1.1 along with Mascot v2.2 software was used for data handling. Aralar1 could be clearly separated, unambiguously identified and characterized from protein extracts of mouse hippocampus by the use of the multidimensional gel electrophoretic steps. The combined sequence coverage of Aralar1 from trypsin, chymotrypsin and subtilisin digestions was 99.85%. The results provide the basis for future studies of Aralar1 at the protein chemical rather than at the immunochemical level in the brain and thus challenge and enable determination of Aralar1 levels required for understanding biological functions in health and disease. [source] New insight into suction and dilution effects in CE coupled to MS via an ESI interface.ELECTROPHORESIS, Issue 10 2009Dilution effect Abstract The hyphenation of CE with MS is nowadays accepted as a powerful analytical approach. As far as ESI, the most common interface, is concerned, one challenge is to provide the most sensitive as well as quantitative information, which is quite a difficult task, as it is linked, among other factors, to suction and dilution effects. In the coaxial ESI configuration, it has been previously demonstrated that suction effect depends on many parameters inherent to the ESI interface geometry, the prevailing ones being the CE capillary protrusion from the interface needle, the sheath liquid (SL) and the overall BGE flow rates and velocity profile. In this paper, dilution effect is studied, as the CE electrolyte is mixed with SL at the interface. Considering peak intensity and efficiency, this effect was studied as a function of the various parameters of the interface (capillary protrusion from the SL tube, nebulizing gas, SL and CE electrolyte flow rates) or of the source (skimmer and ESI voltages, drying gas flow rate and temperature). It appears that the dilution effect seems slightly lower than what can be anticipated from the proportions of the liquid flow rates. This study also indicates that suction effect has to be considered first to better understand the dilution phenomenon, as suction effect leads to an increase in peak intensity, before a dilution effect appears. [source] Electromagnetic torque of a synchronous machine during a single out-of-phase reclosingEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2000A. C. Ammari The adoption of single-pole switching for a radial transmission line which connects large synchronous machines to the power system would submit these machines to repetitive mechanical stress. To evaluate the total mechanical stress, it is first necessary to determine the electromagnetic torque and to evaluate its transient maximum values at reclosing. In this paper, maximum values of the electromagnetic transient torque at single-pole reclosing are first computed using a simplified analytical approach. The analytical results are then validated by numerical simulations and by an experimental test on a laboratory synchronous machine. It will be shown that single-pole reclosing would be, in the worst case, as restricting as three out-of-phase synchronisation. [source] Deposition of chromatin-IgG complexes in skin of nephritic MRL-lpr/lpr mice is associated with increased local matrix metalloprotease activitiesEXPERIMENTAL DERMATOLOGY, Issue 8 2010Annica Hedberg Please cite this paper as: Deposition of chromatin-IgG complexes in skin of nephritic MRL-lpr/lpr mice is associated with increased local matrix metalloprotease activities. Experimental Dermatology 2010; 19: e265,e274. Abstract:, Chromatin-IgG complexes appear as electron dense structures (EDS) in glomerular basement membranes in lupus nephritis. Here, we present results of comparative analyses of the composition of EDS in murine lupus dermatitis and nephritis. One focus was to perform an analytical approach to understand why such complex structures bind skin basement membrane components. Transcription of skin membrane-encoding genes was analysed to see if expression of such genes was increased, eventually indicating that binding capacity of immune complexes increased when dermatitis developed. Variations in matrix metalloprotease 2 (MMP2), MMP9 and Dnase1 mRNA levels and enzymatic activities were correlated with circulatory chromatin-IgG complexes and deposition in skin. We also examined if glomerular deposits of EDS predicted similar deposits in skin of (NZB × NZW)F1 or MRL-lpr/lpr mice, as we observed chromatin-IgG complexes in capillary lumina in skin and glomeruli in both strains. EDS consisting of chromatin fragments and IgG were found sub-epidermally in skin with LE-like lesions of end-stage nephritic MRL-lpr/lpr mice. Dermal MMP-encoding genes were up-regulated during disease progression, and gelatinolytic activity was increased in affected skin. Dnase1 mRNA level and total nuclease activity remained stable in skin during the disease, in contrast to progressive loss of renal Dnase1 mRNA and total renal nuclease activity during development of nephritis. Loss of renal Dnase1 may explain release of chromatin fragments, while increased MMP activity may disrupt membranes making them accessible for chromatin fragment-IgG complexes. Circulatory chromatin-IgG complexes, and up-regulated intradermal MMP activity may be crucial for deposition of immune complexes in skin of lupus-prone mice. [source] Experimental evaluation of creep and fatigue behaviour for microscale solder interconnectFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 2 2007H. LU ABSTRACT This paper presents a novel experimental study for creep and fatigue of solder-interconnects in microstructures. The strains are directly measured in the fillet area of solder-joints with a typical linear dimension of 50 ,m. An analytical approach is developed for calculating shear stress based on the shear strain measurement and the established solder constitutive relations. Also obtained is the strain-rate as well as the separated elastic, plastic and creep components from the measured total strain. The data enables the determination of the strain energy density per temperature cycle for the characterization of the solder joint creep fatigue behaviour. Case studies provide evidence for the shear dominance and the creep fatigue mechanism in thermally induced solder joint deformation in surface-mounted electronic assemblies. Though a similar trend of variation in stress,strain is found in the joints of different solders, the substantial differences in the hysteresis loop area and shape as well as in the creep rate suggest that the solder constitutive parameters should have a profound impact on the creep fatigue endurance of the joints. [source] Glycan profiling of urine, amniotic fluid and ascitic fluid from galactosialidosis patients reveals novel oligosaccharides with reducing end hexose and aldohexonic acid residuesFEBS JOURNAL, Issue 14 2010Cees Bruggink Urine, amniotic fluid and ascitic fluid samples of galactosialidosis patients were analyzed and structurally characterized for free oligosaccharides using capillary high-performance anion-exchange chromatography with pulsed amperometric detection and online mass spectrometry. In addition to the expected endo-,- N- acetylglucosaminidase-cleaved products of complex-type sialylated N -glycans, O -sulfated oligosaccharide moieties were detected. Moreover, novel carbohydrate moieties with reducing-end hexose residues were detected. On the basis of structural features such as a hexose,N -acetylhexosamine,hexose,hexose consensus sequence and di-sialic acid units, these oligosaccharides are thought to represent, at least in part, glycan moieties of glycosphingolipids. In addition, C1 -oxidized, aldohexonic acid-containing versions of most of these oligosaccharides were observed. These observations suggest an alternative catabolism of glycosphingolipids in galactosialidosis patients: oligosaccharide moieties from glycosphingolipids would be released by a hitherto unknown ceramide glycanase activity. The results show the potential and versatility of the analytical approach for structural characterization of oligosaccharides in various body fluids. [source] A selective and sensitive approach to characterize odour-active and volatile constituents in small-scale human milk samplesFLAVOUR AND FRAGRANCE JOURNAL, Issue 6 2007Andrea Buettner Abstract A sensitive and selective analytical approach was developed for the characterization of trace volatile and odorous substances in body fluids. The methodology was successfully applied for identification of more than 40 characteristic odorants in human milk. The technique comprises a modified stir bar sorptive extraction system in combination with two-dimensional gas chromatographic separation and parallel mass spectrometric and olfactometric characterization of the analytes. The present study shows that the technique can be used for both direct extractive sampling and headspace analysis, and that it is applicable for small sample volumes. Copyright © 2007 John Wiley & Sons, Ltd. [source] "The probable industrial origin of archaeological daub at an Iron Age site in northeast Thailand" (Parr and Boyd, 2002): A comment on the inappropriate application of geophysical and geochemical techniques to an archaeological questionGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2003Maria Cotter Parr and Boyd (2002) used colorimetric analysis in combination with geophysical and geochemical techniques to estimate firing temperatures for archaeological daub from an Iron Age site in Thailand. They suggest that the daub was fired at high temperatures and, therefore, is indicative of kiln utilization and increased industrialization during that period in Thailand. They argue that the adoption of a multimethod analytical approach in which the combination of data derived from ICP-MS, X-ray diffraction, and magnetic susceptibility analyses of daub samples, coupled with microscopic and macroscopic examination of samples, enhances the accuracy of their interpretations. While they should be commended for attempting to substantiate their claims using many geophysical and geochemical techniques, their arguments are flawed by the misapplication of the techniques described and/or over-interpretation of the data generated by such techniques. Therefore, Parr and Boyd's (2002:285) point about methodology ("that the combined interpretation of independent measures provides a better estimate of the original firing temperatures of the archaeological material than has hitherto been possible") is made redundant by the lack of scientific rigor applied to the independent measures used for this study. © 2003 Wiley Periodicals, Inc. [source] Stacking velocities in the presence of overburden velocity anomaliesGEOPHYSICAL PROSPECTING, Issue 3 2009Emil Blias ABSTRACT Lateral velocity changes (velocity anomalies) in the overburden may cause significant oscillations in normal moveout velocities. Explicit analytical moveout formulas are presented and provide a direct explanation of these lateral fluctuations and other phenomena for a subsurface with gentle deep structures and shallow overburden anomalies. The analytical conditions for this have been derived for a depth-velocity model with gentle structures with dips not exceeding 12°. The influence of lateral interval velocity changes and curvilinear overburden velocity boundaries can be estimated and analysed using these formulas. An analytical approach to normal moveout velocity analysis in a laterally inhomogeneous medium provides an understanding of the connection between lateral interval velocity changes and normal moveout velocities. In the presence of uncorrected shallow velocity anomalies, the difference between root-mean-square and stacking velocity can be arbitrarily large to the extent of reversing the normal moveout function around normal incidence traveltimes. The main reason for anomalous stacking velocity behaviour is non-linear lateral variations in the shallow overburden interval velocities or the velocity boundaries. A special technique has been developed to determine and remove shallow velocity anomaly effects. This technique includes automatic continuous velocity picking, an inversion method for the determination of shallow velocity anomalies, improving the depth-velocity model by an optimization approach to traveltime inversion (layered reflection tomography) and shallow velocity anomaly replacement. Model and field data examples are used to illustrate this technique. [source] Innovation and Regional Growth in the Enlarged Europe: The Role of Local Innovative Capabilities, Peripherality, and EducationGROWTH AND CHANGE, Issue 4 2005RICCARDO CRESCENZI ABSTRACT In this paper, a formal model for the relationship between innovation and growth in European Union regions is developed drawing upon the theoretical contribution of the systems of innovation approach. The model combines the analytical approach of the regional growth models with the insights of the systemic approach. The cross-sectional analysis, covering all the Enlarged Europe (EU-25) regions (for which data are available), shows that regional innovative activities (for which a specific measure is developed) play a significant role in determining differential regional growth patterns. Furthermore, the model sheds light on how geographical accessibility and human capital accumulation, by shaping the regional system of innovation, interact (in a statistically significant way) with local innovative activities, thus allowing them to be more (or less) effectively translated into economic growth. The paper shows that an increase in innovative effort is not necessarily likely to produce the same effect in all EU-25 regions. Indeed, the empirical analysis suggests that in order to allow innovative efforts in peripheral regions to be as productive as in core areas, they need to be complemented by huge investments in human capital. [source] The SAAPdb web resource: A large-scale structural analysis of mutant proteins,HUMAN MUTATION, Issue 4 2009Jacob M. Hurst Abstract The Single Amino Acid Polymorphism database (SAAPdb) is a new resource for the analysis and visualization of the structural effects of mutations. Our analytical approach is to map single nucleotide polymorphisms (SNPs) and pathogenic deviations (PDs) to protein structural data held within the Protein Data Bank. By mapping mutations onto protein structures, we can hypothesize whether the mutant residues will have any local structural effect that may "explain" a deleterious phenotype. Our prior work used a similar approach to analyze mutations within a single protein. An analysis of the contents of SAAPdb indicates that there are clear differences in the sequence and structural characteristics of SNPs and PDs, and that PDs are more often explained by our structural analysis. This mapping and analysis is a useful resource for the mutation community and is publicly available at http://www.bioinf.org.uk/saap/db/. Hum Mutat 0, 1,9, 2009. © 2009 Wiley-Liss, Inc. [source] An alternative approach to conceptualizing interviews in HRD researchHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 2 2007Jia Wang Qualitative researchers in human resource development (HRD) frequently use in-depth interviews as a research method. Yet reports from qualitative studies in HRD commonly pay little or no analytical attention to the co-construction of interview data. That is, reports of qualitative research projects often treat interviews as a transparent method of data collection, with the contents of answers to interview questions as data that mirror people's views and experiences of a "world out there." In this article, we demonstrate how an ethnomethodological approach to the reanalysis of interview data drawn from a qualitative study in HRD treats the research interview as a socially situated setting in which narrative data are co-constructed by speakers. From this perspective, it is possible to see how speakers produce unstable category descriptions and morally laden portrayals in order to support their claims. We argue that this type of analysis is useful for three reasons: (1) it provides a way to investigate instances in which interview accounts may prove analytically problematic; (2) it makes evident how interview data are produced by illuminating the conversational resources used by both researcher and participant to co-construct descriptions; and (3) it provides a new analytical approach for HRD researchers, who have until now relied primarily on thematic representations of findings derived from inductive analyses of interview data. By using this approach to analyze or reanalyze interview data, researchers may gain further insight into the research topic and the interaction that produced the interview data in a particular socially situated setting. This approach reveals the practical reasoning, identities, and moral assumptions demonstrated in talk by speakers. Such analysis, we argue, assists in HRD theory building in that it contributes to complex interpretations of data that respond to new and different questions, including methodological questions. [source] Analytical approach to the optimal adaptation rate of reconfigurable radio networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2008R. Fraile Abstract Flexible radio resource management schemes are nowadays used within a wide range of systems. However, the optimal selection for their adaptation rate is still an open research issue. This paper presents an analytical approach to such problem, which consists in a combined analysis of the dynamics of the session-arrival process and the estimation of the mean traffic load from network measurements. From this study, it is concluded that both aspects pose an upper limit on the optimal system adaptation rate, being the most restrictive the one depending on the mean traffic load estimation. A specific procedure for deriving such limit on adaptation rate is provided. It is shown that the derived value directly depends on the mean service duration. The application of the whole analysis is illustrated with an example based on a set of measurements from a live network. Copyright © 2008 John Wiley & Sons, Ltd. [source] An analytical approach to the performance evaluation of the balanced gamma switch under multicast traffic,INTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 4 2007Cheng Li Abstract This paper presents the performance evaluation of a new cell-based multicast switch for broadband communications. Using distributed control and a modular design, the balanced gamma (BG) switch features high performance for unicast, multicast and combined traffic under both random and bursty conditions. Although it has buffers on input and output ports, the multicast BG switch follows predominantly an output-buffered architecture. The performance is evaluated under uniform and non-uniform traffic conditions in terms of cell loss ratio and cell delay. An analytical model is presented to analyse the performance of the multicast BG switch under multicast random traffic and used to verify simulation results. The delay performance under multicast bursty traffic is compared with those from an ideal pure output-buffered multicast switch to demonstrate how close its performance is to that of the ideal but impractical switch. Performance comparisons with other published switches are also studied through simulation for non-uniform and bursty traffic. It is shown that the multicast BG switch achieves a performance close to that of the ideal switch while keeping hardware complexity reasonable. Copyright © 2006 John Wiley & Sons, Ltd. [source] High isolation microstrip GaN-HEMT Single-FET SwitchINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 4 2010Walter Ciccognani Abstract In this contribution an analytical approach to the design of high-isolation microwave transmission line-resonated switches is presented. Simulated and measured performance of a GaN HEMT single-FET switch cell topology and the one of a complete SPDT using the proposed approach are presented to demonstrate the approach feasibility and effectiveness. The resulting SPDT, operating at X Band, is featured by 1 dB insertion loss, isolation better than 37 dB all over the operating bandwidth and a power handling capability higher than 39 dBm. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 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