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Multiple-source disturbances exist in the polarization sensor, which severely affect the sensor accuracy and stability. Hence, the disturbance analysis plays a vital role in improving the sensor orientation performance. This paper aims to present a novel sensor error model, a disturbances quantitative analysis, a calibration and performance test of polarization sensor based on a polarizing beam splitter.

By combining with the sensor coefficient errors, the Azimuth of Polarization (AoP) error model and the Degree of Polarization (DoP) error model are established, respectively. In addition, the multiple-source disturbances are classified, while the influence on the orientation accuracy is quantitative analyzed. Moreover, the least square optimization algorithm is employed to calibrate the sensor coefficients. Finally, an outdoor test is carried out to test the sensor long-term accuracy.

The theoretical analysis and numerical simulations illustrate that the sensor accuracy is closely related to the disturbances. To eliminate the influence of the disturbances, the least square optimization algorithm, which can minimize the sum of squares of the residual difference of AoP and DoP, is used to calibrate the sensor coefficients. The outdoor test indicates that the sensor can maintain long-term accuracy and stability.

The main contribution of this paper is to establish a novel sensor error model, where the sensor coefficient errors are introduced. In addition, the disturbances are classified and analyzed to evaluate the orientation accuracy of the sensor.

The purpose of this study is to improve the performance of hollow fiber membrane and improve the separation efficiency.

By establishing a mathematical model of hollow fiber membrane gas separation, the influences of parameters such as pressure difference between the inside and outside of the filament, initial oxygen concentration of intake air, intake air flow rate and back pressure outside the filament on the polarization coefficient were analyzed, so as to explore the degree of influence of operating parameters on the concentration polarization, and put forward a technical scheme to reduce the concentration polarization.

Factors such as pressure difference between the inside and outside of the filament, initial oxygen concentration of intake air, intake air flow rate and back pressure outside the filament have a certain effect on the polarization coefficient. Among them, the polarization coefficient is positively correlated with pressure difference inside and outside the filament, initial oxygen concentration of intake air and back pressure outside the filament, and is negatively correlated with intake air flow.

Negative pressure suction on the permeation side can be used to increase the membrane permeation flow rate and reduce the concentration polarization.

The influence of concentration polarization on membrane performance is reduced by controlling various factors.

The purpose of this paper is to investigate the relationships between measures of ethnic and religious heterogeneity on the one hand and measures of inequality and redistribution on the other, using state‐level US data.

The relationship between ethnic/religious heterogeneity and inequality/redistribution is estimated, first, with ordinary least squares (OLS) and then with generalized method of moments (GMM). The principal explanatory variables for inequality and redistribution in the study are ethnic and religious polarization and fractionalization measures.

It is found that inequality is positively associated with polarization and has an inverse‐U relationship with fractionalization. These findings are bolstered by findings of indirect effects of ethnic and religious heterogeneity on inequality through their influence on welfare programs.

This is the first paper investigating the magnitude of possible direct and indirect effects of ethnic and religious heterogeneity on income inequality using US data.

A growing polarization of society accompanied by an erosion of the middle class is receiving increasing attention in recent German economic and social policy discussion. Our study contributes to this discussion in two ways: First, on a theoretical level we propose extended multidimensional polarization indices based on a constant elasticity of substitution (CES)-type well-being function and present a new measure to multidimensional polarization, the mean minimum polarization gap, 2DGAP. This polarization intensity measure provides transparency with regard to each single attribute, which is important for targeted policies, while at the same time respecting their interdependent relations. Second, in an empirical application, time is incorporated, in addition to the traditional income measure, as a fundamental resource for any activity. In particular, genuine personal leisure time will account for social participation in the sense of social inclusion/exclusion and Amartya Sen’s capability approach.

Instead of arbitrarily choosing the attribute parameters in the CES well-being function, the interdependent relations of time and income are evaluated by the German population. With the German Socio-Economic Panel (GSOEP) and detailed time use diary data from the German Time Use Surveys (GTUSs) 1991/1992 and 2001/2002, we quantify available and extended multidimensional polarization measures as well as our new approach to measuring the polarization of the working poor and affluent in Germany.

There are three prominent empirical results: Genuine personal leisure time in addition to income is an important and significant polarization attribute. Compensation is of economic and statistical significance. The new minimum 2DGAP approach reveals that multidimensional polarization increased in the 1990s in Germany.

The relationship between income inequality and polarization is an empirical fact: a change in equality might occur together with a change in polarization. At the same time, polarization might emerge while inequality remains constant. The outcome of this process entails relevant information on the evolution of the income distribution. We exploit the LIS database to perform a relative distribution analysis for six European countries. Our aim is describing how disposable income distributions evolved over time. The results indicate that polarization increased in all the considered countries, being the largest in the United Kingdom and the smallest in Italy. Nonetheless, in all the countries downgrading prevails over upgrading: the relevance of the middle class getting poorer is larger than the one of the middle class getting richer.

This paper aims to study, by means of an empirical approach, how monetary policy might affect the distribution of individual income.

After describing the channels through which monetary policy could impinge on income distribution, the authors carry out a panel analysis of 62 countries that control their monetary policy for the period 1996–2015.

Using two possible proxy variables for monetary policy (the monetary aggregate M3 and the real interest rates), the results reveal a significant positive relationship between real interest rates and income inequality measured through the market Gini coefficient and polarization ratios. The findings suggest that central bankers should be more aware of the redistributive effects of monetary policy.

It should be mentioned the major challenge of data limitation in the empirical investigation on the relationship between monetary policies and inequalities.

The empirical evidence presented in this paper supports the premise that central bankers should not ignore the unintended redistributive consequences of their actions. In this regard, it is worth noting that if, in addition to price stability, central banks are also responsible for financial stability; the rationale behind central bank independence needs to be reconsidered.

An outstanding feature of the paper is its sample size and the variety of countries included in the sample, which includes countries from all continents and with very different levels of economic development. Also, unlike papers based on forecasting modeling – e.g. Vector autoregression (VAR) or Structural vector autoregression (SVAR) models, the study follows an explanatory approach, including not only monetary variables, but also a series of regressors that may have a meaningful and significant impact on inequality, according to a wide literature.

The purpose of this paper is to study the effect of firm-specific capabilities on performance in regional polarization.

The study develops and tests a theoretical model relating regional economic characteristics and firm-specific capabilities to performance. Based on a survey conducted by the World Bank, data on 17,196 firms in 20 Latin American countries were constructed and analysed.

The performance impacts of a firm's operations capability, technological capability and marketing capability were all found to be strengthened by operating in the Brazil-group economies – more favorable economic environments.

The findings confirm empirically that regional polarization has an important influence on firm performance. Moreover, these findings suggest a more nuanced understanding of the effects of firm-specific capabilities on firm performance. Some types of economies foster the effects of firm-specific capabilities and offer a favorable economic and institutional environment which can greatly stimulate firms to re-configure and develop their skills and improve their global competitiveness, leading to a better firm performance.

As Robles has noted, “Given that polarization is a recent [development], there is [a] paucity of research on how firms cope with either expansionary or depressed domestic and global market conditions. There is little evidence of effective strategies and [their] performance implications in expansionary and contracting markets in the region.” This study addresses this important gap in the literature by demonstrating that operating in a country grouped with Brazil-type economies was positively related with firm performance.

The purpose of this study is to develop an efficient model to solve the electromagnetic forward problem using a novel semi-analytical approach to compute the electromagnetic fields because of the presence of a scatterer.

The proposed model involves a novel formulation of a complete orthonormal set of radiating/nonradiating polarization currents. Furthermore, an integral equation-based representation is derived, and the appropriate boundary conditions are imposed to get the scattered electromagnetic field. An error term is introduced to evaluate the obtained results.

The proposed model was tested using several examples at different frequencies. The results of this study show that the novel representation exhibits fast convergence behavior and achieves highly accurate results, when compared to the results provided by the transmission line method.

The derived formulations presented in this study are significant in the electromagnetic forward modelling field because of the meaningful physical representation they provide. This is an important aspect that leads to precise calculation of electromagnetic fields for various applications.

This paper has two purposes: to use polarisation to identify variations in loyalty and to apply polarisation to an important non‐brand attribute, price.

A comprehensive revealed preference data set of wine purchases is used to apply polarisation. Polarisation was defined in two ways: as a function of the beta binomial distribution (BBD) to give a measure of loyalty for an alternative; and as a function of the Dirichlet multinomial distribution (DMD) to give a baseline level of loyalty. Variations were identified by analysing the differences between the BBD and DMD.

Polarisation was shown to be one way of identifying variation across price tiers. In the empirical example used, the DMD model is violated with the price tiers not being directly substitutable with one another. Buyers show excess loyalty towards the lowest and highest price tier levels. One tier shows “change‐of‐pace” loyalty. Small brands do better when they focus on high loyalty tiers, middle brands compete in the change‐of‐pace tier and large brands do well across all tiers.

Very little work has been undertaken into price tier loyalty and no known empirical research has been undertaken into behavioural loyalty to price tiers in wine. Very little empirical research has considered the association between excess loyalty for attribute levels (such as price tiers) and the existence of niche, change‐of‐pace and reinforcing brands.

To provide a detailed investigation about methods commonly used for the computation of high‐frequency electromagnetic fields in the vicinity of obstacles that can reflect or diffract them. This is useful to create an elementary block that can be used to evaluate with a high accuracy the propagation of high‐frequency electromagnetic waves in real urban environment.

The approach is based on a realistic application of the asymptotic theory of the uniform theory of diffraction. Therefore, the effect of material roughness and its electromagnetic properties on the reflection are taken into account.

Provides information about the mechanisms involved in electromagnetic field propagation in urban environment, and the relative importance of each one.

In urban environment the buildings obviously have finite dimensions. The diffraction equations examined in the paper are strictly valid only in the case of infinite wedges; therefore, the behaviour of real building edges has not been taken rigorously into account.

A source of information for researchers interested in the development of a simulator for the electromagnetic propagation in urban environment.

This paper is aimed at providing to researchers, in a more comprehensive way, all information needed for the study of electromagnetic propagation in an environment containing many close scatterers.