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Non-standard Dirac adjoint spinor: The emergence of a new dual

In this present communication we provide a new derivation of the Dirac dual structure by employing a different approach from the originally proposed. Following a general and rigorous mathematical process to compute the dual structure, we investigate if is possible to break the existing "rigidity" in its primordial formulation. For this task, firstly, we look towards to understand the core of the Dirac spinors construction and then, we suggest to built an alternative dual structure for the Dirac spinor, which preserve an invariant norm under any $SL(2,\mathcal{C})$ transformation. Finally, we verify if the prominent physical contents are maintained or if it is affected by such construction.Comment: 7 pages, 0 figure

Factors behind the convergence of economic performance across U.S. states

The rolling recessions of the 1970s and 1980s were characterized by industry and region specific shocks that led to large dispersions in the economic performance of regions across the U.S. The 1970s were primarily impacted by sharply rising energy prices that hit the manufacturing states hard while stimulating growth in the energy states.> ; The 1980s began with declines in the Farm Belt, followed by declines in the Energy Belt, the Rust (manufacturing) Belt, and finally, due to declines in defense spending, a decline in the Gun Belt. Simple measures of regional dispersion such as the population-weighted variance of job growth across states show that the economic dispersion was historically high during these two decades.> ; The 1990s saw a continuous decline in regional economic dispersion and the 2000s has seen historically low levels of dispersion. Perhaps the biggest surprise this decade has been the low levels of dispersion of economic performance over the past several years given the significant energy price shocks and the depth of the national economic recession. In this paper, we look at the likely causes of economic dispersion across regions and test for the major influences both in the rise of dispersion in the 1970s and 1980s and the subsequent fall in the 1990s and 2000s. Major factors that we test include state industrial structure, oil price shocks and bank integration.Regional economics ; Industries ; Economic development

is Social Security Part of the Social Safety Net?

Building on the existing literature that examines the extent of redistribution in the Social Security system as a whole, this paper focuses more specifically on how Social Security affects the poor. This question is important because a Social Security program that reduces overall inequality by redistributing from high income individuals to middle income individuals may do nothing to help the poor; conversely, a program that redistributes to the poor may nonetheless be regressive according to broader measures if it also redistributes from middle to upper income households. We have four major findings. First, as we expand the definition of income to use more comprehensive measures of well-being, we find that Social Security becomes less progressive. Indeed, when we use an "endowment" defined by potential labor earnings at the household level, rather than actual earnings at the individual level, we find that Social Security has virtually no effect on overall inequality. Second, we find that this result is driven largely by the lack of redistribution across the middle and upper part of the income distribution, so it masks some small positive net transfers to those at the bottom of the lifetime income distribution. Third, in cases where redistribution does occur, we find it is not efficiently targeted: many high income households receive positive net transfers, while many low income households pay net taxes. Finally, the redistributive effects of Social Security change over time, and these changes depend on the income concept used to classify someone as "poor".

Design and Experimental Validation of a Software-Defined Radio Access Network Testbed with Slicing Support

Network slicing is a fundamental feature of 5G systems to partition a single network into a number of segregated logical networks, each optimized for a particular type of service, or dedicated to a particular customer or application. The realization of network slicing is particularly challenging in the Radio Access Network (RAN) part, where multiple slices can be multiplexed over the same radio channel and Radio Resource Management (RRM) functions shall be used to split the cell radio resources and achieve the expected behaviour per slice. In this context, this paper describes the key design and implementation aspects of a Software-Defined RAN (SD-RAN) experimental testbed with slicing support. The testbed has been designed consistently with the slicing capabilities and related management framework established by 3GPP in Release 15. The testbed is used to demonstrate the provisioning of RAN slices (e.g. preparation, commissioning and activation phases) and the operation of the implemented RRM functionality for slice-aware admission control and scheduling

Type-4 spinors: transmuting from Elko to single-helicity spinors

In this communication we briefly report an unexpected theoretical discovery which emerge from the mapping of Elko mass-dimension-one spinors into single helicity spinors. Such procedure unveils a class of spinor which is classified as type-4 spinor field within Lounesto classification. In this paper we explore the underlying physical and mathematical contents of the type-4 spinor.Comment: 9 pages, 0 figure

On the bilinear covariants associated to mass dimension one spinors

In this paper we approach the issue of Clifford algebra basis deformation, allowing for bilinear covariants associated to Elko spinors which satisfy the Fierz-Pauli-Kofink identities. We present a complete analysis of covariance, taking into account the involved dual structure associated to Elko. Moreover, the possible generalizations to the recently presented new dual structure are performed.Comment: 9 pages, 0 figure

Space station integrated wall design and penetration damage control

A methodology was developed to allow a designer to optimize the pressure wall, insulation, and meteoroid/debris shield system of a manned spacecraft for a given spacecraft configuration and threat environment. The threat environment consists of meteoroids and orbital debris, as specified for an arbitrary orbit and expected lifetime. An overall probability of no penetration is calculated, as well as contours of equal threat that take into account spacecraft geometry and orientation. Techniques, tools, and procedures for repairing an impacted and penetrated pressure wall were developed and tested. These techniques are applied from the spacecraft interior and account for the possibility of performing the repair in a vacuum. Hypervelocity impact testing was conducted to: (1) develop and refine appropriate penetration functions, and (2) determine the internal effects of a penetration on personnel and equipment