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The paper examines inter-regional insurance and redistribution of Russia's fiscal system from 1995 to 2007. We use non-parametric methods for robustness and to tackle econometric problems of endogeneity and poolability. We will also use several specifications of variables. We find that the Russian inter-regional insurance system should be considered a stabilizing scheme against tax income and budget expenditure shocks, rather than against gross product or population income shocks, as typically assumed in Literature considering data of other countries. Furthermore, we find evidence that the differences in the insurance estimates are mainly due to Federation-wide policy changes rather than a result of asymmetric treatment of regions. Comparative Economic Studies (2012) 54, 633-660. doi: 10.1057/ces.2012.16; published online 3 May 2012 Keywords: inter-regional insurance, Russia, fiscal federalism, non-parametric analysis JEL Classifications: P35, H77, C14, INTRODUCTION According to Oates (1999), three roles for intergovernmental transfers are emphasized in fiscal Federalism literature: internalization of spillover benefits over jurisdictions, fiscal equalization across jurisdictions and an improved overall [...]

Generalized Linear Latent Variables Models (GLLVM) enable the modeling of relationships between manifest and latent variables, where the manifest variables are distributed according to a distribution of the exponential family (e.g., binomial or normal) and to the multinomial distribution (for ordinal manifest variables). These models are widely used in social sciences. To test the appropriateness of a particular model, one needs to define a goodness-of-fit test statistic (GFI). In the normal case, one can use a likelihood ratio test or a modified version proposed by Satorra and Bentler (2001) (S&B GFI) that compares the sample covariance matrix to the estimated covariance matrix induced by the model. In the binary case, Pearson-type test statistics can be used if the number of observations is sufficiently large. In the other cases, including the case of mixed types of manifest variables, there exists GFI based on a comparison between a pseudo sample covariance and the model covariance of the manifest variables. These types GFI are based on latent variable models that suppose that the manifest variables are themselves induced by underlying normal variables (underlying variable approach). The pseudo sample covariance matrices are then made of polychoric, tetrachoric or polyserial correlations. In this article, we propose an alternative GFI that is more generally applicable. It is based on some distance comparison between the latent scores and the original data. This GFI takes into account the nature of each manifest variable and can in principle be applied in various situations and in particular with models with ordinal, and both discrete and continuous manifest variables. To compute the p-value associated to our GFI, we propose a consistent resampling technique that can be viewed as a modified parametric bootstrap. A simulation study shows that our GFI has good performance in terms of empirical level and empirical power across different models with different types of manifest variables. This article has supplementary material online. KEY WORDS: Bagging; Distance measures; Exponential family; h-likelihood; Laplace approximation; Latent scores; LISREL; Multinomial distribution; Parametric bootstrap; U-statistics.

The main objective of this research is to compare different irrigation methods based upon a parametric evaluation system in an area of 29,300 ha in the Abbas plain located in the Elam Province, in the west of Iran. The soil properties of the study area such as texture, depth, electrical conductivity, drainage, calcium carbonate content, and slope were derived from a semidetailed soil study carried out on the Abbas Plain on a scale of 1:20,000. Once the soil properties were analyzed and evaluated, suitability maps were generated for surface, sprinkle, and drip irrigation methods using remote sensing techniques and geographic information system. The obtained results showed that for 16,125 ha (55.03%) of the study area surface irrigation method was highly recommended; whereas for 16,600 ha (56.66%) of the study area a sprinkle irrigation method would provide to be extremely efficient and suitable; moreover, it was found that 15,425 ha (52.65%) of the study area was highly suitable for drip irrigation methods; however, one soil series coded 9 and covering an area of 2,150 ha (7.34%) was incompatible for sprinkle and surface irrigation systems. For drip irrigation systems the unsuitable lands did not exist in this zone. The results demonstrated that by applying sprinkle irrigation instead of surface and drip irrigation methods, the arability of 21,250 ha (72.53%) in the Abbas Plain will improve. In addition by applying drip irrigation instead of surface and sprinkle irrigation methods, the land suitability of 6,275 ha (21.42%) of this plain will improve. The comparison of the different types of irrigation techniques revealed that the sprinkle and drip irrigation methods were more effective and efficient than the surface irrigation methods for improving land productivity. It is of note, however, that the main limiting factor in using either surface and/or sprinkle irrigation methods in this area is soil texture and the main limiting factor in using drip irrigation methods were soil calcium carbonate content and soil texture. DOI: 10.1061/(ASCE)IR.1943-4774.0000142 CE Database subject headings: Irrigation; Sprinkler irrigation; Trickle irrigation; Parameters; Iran. Author keywords: Surface irrigation; Sprinkle irrigation; Drip irrigation; Land suitability evaluation; Parametric method; Soil series.

An extensive experimental analysis on the subject of the unsteady periodic flow in a high subsonic high pressure (HP) turbine stage has been carried out at the Laboratorio di Fluidodinamica delle Macchine of the Politecnico di Milano (Italy). In this paper the aerodynamic blade row interaction in HP turbines, enforced by increasing the stator and rotor blade loading and by reducing the stator-rotor axial gap, is studied in detail. The time-averaged three-dimensional flowfield in the stator-rotor gap was investigated by means of a conventional five-hole probe for the nominal (0 deg) and highly positive (+22 deg) stator incidences. The evolution of the viscous flow structures downstream of the stator is presented to characterize the rotor incoming flow. The blade row interaction was evaluated o, the basis of unsteady aerodynamic measurements at the rotor exit. performed with a fast-response aerodynamic pressure probe. Results show a strong dependence of the time-averaged and phase-resolved flowfield and of the stage performance on the stator incidence. The structure of the vortex-blade interaction changes significantly as the magnitude of the rotor-inlet vortices increases, and very different residual traces of the stator secondary flows are found downstream of the rotor. On the contrary, the increase in rotor loading enhances the unsteadiness in the rotor secondary flows but has a little effect on the vortex-vortex interaction. For the large axial gap, a reduction of stator-related effects at the rotor exit is encountered when the stator incidence is increased as a result of the different mixing rate within the cascade gap. [DOI: 10.1115/1.2987236]

This paper presents a new approach for performing fast multiobjective optimization of the design of moving nonlinear electromagnetic (EM) devices using parametric reduced order EM field models. The approach minimizes the high computational costs that arises from the frequent evaluation of large scale spatially discretized EM field models during the optimization process run. The performance of the proposed approach is demonstrated by carrying out a multiobjective design optimization of an electromagnetic device with a moving component and nonlinear material properties. Index Terms--Electromagnetic (EM) devices, model order reduction (MOR), multiobjeetive optimization, parametric reduced order models (PROM).

A procedure that speeds up parametric modelling is presented. With the help of manifolds and differential geometry it is possible to use a single mesh for problems corresponding to different parameter values. Index Terms--Differential geometry, optimization, parametric modelling.

This paper focuses on the parametric modeling and optimization of the chemical vapor deposition (CVD) process for the deposition of thin films of silicon from silane in a vertical impinging CVD reactor. The parametric modeling using radial basis function for various functions, which is related to the deposition rate and uniformity of the thin films, is studied. These models are compared and validated with additional sampling data. Based on the parametric models, different optimization formulations for maximizing the deposition rate and the working areas of thin film are performed. [DOI: 10.1115/1.3063689]

A primary focus of an increasing number of scientific studies is to determine whether two exposures interact in the effect that they produce on an outcome of interest. Interaction is commonly assessed by fitting regression models in which the linear predictor includes the product between those exposures. When the main interest lies in the interaction, this approach is not entirely satisfactory, because it is prone to (possibly severe) bias when the main exposure effects or the associations between outcome and extraneous factors are misspecified. In this article we consider conditional mean models with identity or log link that postulate the statistical interaction in terms of a finite-dimensional parameter but are otherwise unspecified. We show that estimation of the interaction parameter often is not feasible in this model, because it requires nonparametric estimation of auxiliary conditional expectations given high-dimensional variables. We thus consider multiply robust estimation under a union model that assumes that at least one of several working submodels holds. Our approach is novel in that it makes use of information on the joint distribution of the exposures conditional on the extraneous factors in making inferences about the interaction parameter of interest. In the special case of a randomized trial or a family-based genetic study in which the joint exposure distribution is known by design or by Mendelian inheritance, the resulting multiply robust procedure leads to asymptotically distribution-free tests of the null hypothesis of no interaction on an additive scale. We illustrate the methods through simulation and analysis of a randomized follow-up study. KEY WORDS: Double robustness: Gene-environment interaction: Gene-gene interaction: Longitudinal data: Semi parametric inference.

This paper deals with systems governed by the Mathieu-Duffing equation, with a time-dependent coefficient of the linear term and a constant, not necessarily small coefficient of the cubic term. This coefficient can be positive or negative. The method of strained parameters applied to a linear system governed by the Mathieu equation is extended to a strongly nonlinear system. As a result, the curves corresponding to the parameter values at which periodic solutions exist are obtained. It is shown that they strongly depend on the value of the coefficient of nonlinearity and the initial conditions. The corresponding parameter planes are plotted. Numerical integrations are carried out to confirm the analytical results. [DOI: 10.1115/1.3112722] Keywords: Mathieu-Duffing equation, strong nonlinearity, periodic solution

Byline: Norio Matsuki In this paper, problems of current computer aided design (CAD) systems are discussed. One problem is the existence of tolerance. Because of tolerance, geometric operations become unstable and CAD data-exchange becomes a troublesome task. The second problem is CAD data durability. There is almost no compatibility between CAD data of different versions of the same system. Thus, users of CAD systems are confronted with great difficulties when they try to keep CAD data for a long time. As a solution to these problems, a CAD kernel based on history-based parametrics is proposed.

Byline: Shuming Gao This paper presents an approach to real-time exchanging of parametric feature models and assembly models among heterogeneous CAD systems. In the approach, we directly exchange every feature operation or assembly operation rather than the models based on an instantaneous translation mechanism between system modelling operations (SMOs) and neutral modelling commands (NMCs). To effectively support the translation between SMOs and NMCs, an object-oriented representation of NMCs is given.

Byline: Soonhung Han The macro-parametric method is for the exchange of CAD models, where the history of modelling commands is translated. Five well-known commercial CAD systems have been analysed to arrive at the core commands set. Primitive functions of a CAD system have been implemented in the TransCAD system. New technologies such as ontology or web services can improve the macro-parametric approach against the problems like persistent naming.

The parametric study on the effects of various design parameters on the sound-pressure-level distribution for a miniature loudspeaker in a cellular phone is reported. The results from analysis of role of each design parameter could be used to improve the overall sound-pressure-level performance over the midfrequency spectrum.

While mechanical stimulation of cells seeded within scaffolds is widely thought to be beneficial, the amount of benefit observed is highly variable between experimental systems. Although studies have investigated specific experimental loading protocols thought to be advantageous for cartilage growth, less is known about the physical stimuli (e.g., pressures, velocities, and local strains) cells experience during these experiments. This study used results of a literature survey, which looked for patterns in the efficacy of mechanical stimulation of chondrocyte seeded scaffolds, to inform the modeling of spatial patterns of physical stimuli present in mechanically stimulated constructs. The literature survey revealed a large variation in conditions used in mechanical loading studies, with a peak to peak strain of 10% (i.e., the maximum amount of deformation experienced by the scaffold) at 1 Hz on agarose scaffolds being the most frequently studied parameters and scaffold. This loading frequency was then used as the basis for simulation in the finite element analyses. 2D axisymmetric finite element models of 2 X 4 [mm.sup.2] scaffolds with 360 modulus/permeability, combinations were constructed using COMSOL MULTIPHYSICS software. A time dependent coupled pore pressure/effective stress analysis was used to model fluid/solid interactions in the scaffolds upon loading. Loading was simulated using an impermeable frictionless loader on the top boundary with fluid and solid displacement confined to the radial axis. As expected, all scaffold materials exhibited classic poro-elastic behavior having pressurized cores with low fluid flow and edges with high radial fluid velocities. Under the simulation parameters of this study, PEG scaffolds had the highest pressure and radial liquid velocity but also the lowest shear stress and radial strain. Chitosan and KLD-12 simulated scaffold materials had the lowest radial strains and fluid velocities, with collagen scaffolds having the lowest pressures. Parametric analysis showed maximum peak pressures within the scaffold to be more dependent on scaffold modulus than on permeability and velocities to depend on both scaffold properties similarly. The dependence of radial strain on permeability or modulus was more complex; maximum strains occurred at lower permeabilities and moduli, and the lowest strain occurred at the stiffest most permeable scaffold. Shear stresses within all scaffolds were negligible. These results give insight into the large variations in metabolic response seen in studies involving mechanical stimulation of cell-seeded constructs, where the same loading conditions produce very different results due to the differences in material properties. [DOI: 10.1115/1.3128672] Keywords: mechanobiology, cartilage, tissue engineering, bioreactor, poro-elastic model, physical stimuli, cyclic compression, mechanical loading, scaffold analysis