Weighted norm inequalities for the bilinear maximal operator on variable Lebesgue spaces

We extend the theory of weighted norm inequalities on variable Lebesgue spaces to the case of bilinear operators. We introduce a bilinear version of the variable \A_\pp condition, and show that it is necessary and sufficient for the bilinear maximal operator to satisfy a weighted norm inequality. Our work generalizes the linear results of the first author, Fiorenza and Neugebauer \cite{dcu-f-nPreprint2010} in the variable Lebesgue spaces and the bilinear results of Lerner {\em et al.} \cite{MR2483720} in the classical Lebesgue spaces. As an application we prove weighted norm inequalities for bilinear singular integral operators in the variable Lebesgue spaces.Comment: Revised based on anonymous referee's reports. A number of typos and small errors corrected. One conjecture added to introductio

Embeddings between grand, small and variable Lebesgue spaces

We give conditions on the exponent function $p(\cdot)$ that imply the existence of embeddings between grand, small and variable Lebesgue spaces. We construct examples to show that our results are close to optimal. Our work extends recent results by the second author, Rakotoson and Sbordone.Comment: Final version to appear in Math. Note

Growing the future of agriculture: an examination of knowledge-sharing and community building in the fresh produce and floral council

This study examines knowledge-sharing practices within a community of practice (CoP) through a case study of the Fresh Produce and Floral Council (FPFC). The study sought to investigate how the FPFC promoted agricultural knowledge and expertise, impacted its members\u27 social relationships and knowledge-sharing practices, communicated clear roles and expectations, and provided valuable and accessible resources. A mixed-methods approach was employed to investigate the research questions, which involved conducting a survey and utilizing descriptive statistics, frequencies, and Spearman correlations to analyze both the Likert scale and open-ended responses. The findings suggested that the FPFC has a knowledge-sharing culture promoting active participation and collaboration among members, with room for improvement in knowledge-sharing practices. Additionally, FPFC positively impacts members\u27 social relationships and prioritizes knowledge-sharing, with a need for further education and promotion of these benefits. Also, clear communication of roles and expectations is essential in any CoP. There may be a need to further clarify the community\u27s goals and purpose to ensure member engagement and alignment. Finally, members perceived FPFC\u27s resources as valuable and relevant, but there is a need for improvement in their accessibility and availability. Overall, the study provided valuable insights for developing new methods of knowledge-sharing and onboarding within the agriculture industry to address the aging crisis and ensure the industry\u27s future. Thus, it was essential to explore the value of knowledge-sharing practices and technology for communication within the community to contribute to developing virtual CoPs enabling knowledge transfer and relationship building for agriculture professionals

Climatology of Rainfall Distribution and Asymmetries of Tropical Cyclones: A Global Perspective

Estimating the magnitude of tropical cyclone (TC) rainfall at different landfalling states is an important aspect of the TC forecast that directly affects the level of response from emergency managers in coastal areas. This research analyses the spatial distribution of the rainfall magnitude in tropical cyclones (TCs) at different stages over global oceans. The research’s central hypothesis is that TC rainfall exhibits distinct features in the long-term satellite dataset due to the evolution of the spatial distribution, radial variation, and asymmetries at the stages before, during, and after landfall. The resulting patterns are analyzed through a statistical approach that takes advantage of a 20-year global satellite database of rainfall retrievals from the TRMM/GPM constellation, with the aim to achieve two main objectives: 1) The first objective was to explore the global trends of TC rainfall rates using observational evidence provided by a satellite-based climatology. Results indicate there is an increasing trend in the global average TC rainfall rate of about 1.3% per year, with a more pronounced trend in the northern hemisphere than in the southern hemisphere. 2) The second objective was to examine the spatial distribution of the magnitude and axisymmetric intensity profiles of rainfall over the six TC-prone basins. The obtained differences were quantitatively investigated in terms of geographic location, sub-regions within the storm, and TC intensities. Results indicate that major hurricanes in the Atlantic basin exhibit heavier inner-core rainfall rates than those in any other basins, and this difference is highly correlated to specific environmental conditions. Overall, with the achievement of the above-described objectives, this document identifies and summarizes the dominant factors that control rainfall distribution in global TCs, mainly focused on the differences during landfilling processes

Heavier inner-core rainfall of major hurricanes in the North atlantic basin than in other global basins

Based on 19 years of precipitation data collected by the Tropical Rainfall Measuring Mission (TRMM) and the Global Precipitation Measurement (GPM) mission, a comparison of the rainfall produced by tropical cyclones (TCs) in different global basins is presented. A total of 1789 TCs were examined in the period from 1998 to 2016 by taking advantage of more than 47 737 observations of TRMM and GPM 3B42 multisatellite-derived rainfall amounts. The axisymmetric component of the TC rainfall is analyzed in all TC-prone basins. The resulting radial profiles show that major hurricanes in the Atlantic basin exhibit significantly heavier inner-core rainfall rates than those in any other basins. To explain the possible causes of this difference, rainfall distributions for major hurricanes are stratified according to different TC intensity and environmental variables. Based on the examination of these parameters, we found that the stronger rainfall rates in the Atlantic major hurricanes are associated with higher values of convective available potential energy, drier relative humidity in the low to middle troposphere, colder air temperature at 250 hPa, and stronger vertical wind shear than other basins. These results have important implications in the refining of our understanding of the mechanisms of TC rainfall

Global increase in tropical cyclone rain rate

Theoretical models of the potential intensity of tropical cyclones (TCs) suggest that TC rainfall rates should increase in a warmer environment but limited observational evidence has been studied to test these hypotheses on a global scale. The present study explores the general trends of TC rainfall rates based on a 19-year (1998–2016) time series of continuous observational data collected by the Tropical Rainfall Measuring Mission and the Global Precipitation Measurement mission. Overall, observations exhibit an increasing trend in the average TC rainfall rate of about 1.3% per year, a fact that is contributed mainly by the combined effect of the reduction in the inner-core rainfall rate with the increase in rainfall rate on the rainband region. We found that the increasing trend is more pronounced in the Northwestern Pacific and North Atlantic than in other global basins, and it is relatively uniform for all TC intensities. Further analysis shows that these trends are associated with increases in sea surface temperature and total precipitable water in the TC environment

ORION - Crew Module Side Hatch: Proof Pressure Test Anomaly Investigation

The Orion Multi-Purpose Crew Vehicle program was performing a proof pressure test on an engineering development unit (EDU) of the Orion Crew Module Side Hatch (CMSH) assembly. The purpose of the proof test was to demonstrate structural capability, with margin, at 1.5 times the maximum design pressure, before integrating the CMSH to the Orion Crew Module structural test article for subsequent pressure testing. The pressure test was performed at lower pressures of 3 psig, 10 psig and 15.75 psig with no apparent abnormal behavior or leaking. During pressurization to proof pressure of 23.32 psig, a loud 'pop' was heard at ~21.3 psig. Upon review into the test cell, it was noted that the hatch had prematurely separated from the proof test fixture, thus immediately ending the test. The proof pressure test was expected be a simple verification but has since evolved into a significant joint failure investigation from both Lockheed Martin and NASA

Matriz de Contabilidad Social Tributaria 1997

This paper documents the features of a 1997 Social Accounting Matrix (SAM) with emphasis on tax accounts for Colombia. We present four different formats according to different definitions of the Good and Services Account: (i) product-product, (ii) activity-product, (iii) use and supply tables separated, and (iv) multiplier-analysis oriented. Using the latter we compare the impact of three identical exogenous shocks over three key sectors of the Colombian economy in 1997: the coffee sector, the oil sector and the gross fixed capital formation account. We find that the most beneficial shock regarding household income and government revenues comes from an exogenous shock on the coffee sector

Avances en el indicador de perdurabilidad empresarial

El Grupo de Investigación en Perdurabilidad Empresarial de la Facultad de Administración de la Universidad del Rosario ha venido trabajando para encontrar un factor cuantitativo financiero de medición que permita apoyar la metodología para determinar si una empresa y/o sector estratégico1 es perdurable. Contar con este indicador facilita la medición del hacinamiento cuantitativo y permite poner en comparación, bajo términos unificados, el resultado de dicha herramienta con los resultados fácilmente observables a través de la investigación y consultoría cualitativa. Más de 80 sectores estratégicos han sido abordados para realizar el análisis de hacinamiento, una de las primeras dificultades que surge es la determinación del indicador cuantitativo de evaluación, ya que en la mayoría de los casos los empresarios no cuentan con indicadores no financieros para realizar una comparación frente a sus rivales directos