Understanding and overcoming the "positive profits with negative surplus-value" paradox

ABSTRACT This paper explains the "positive profits with negative surplus-value" example of Steedman (1975) and shows that while in joint production systems individual labour values can be negative, the claim that the total labour embodied in the surplus product of the economy (surplus-value) can also be negative is based on assumptions that have no economic meaning (such as negative activity levels).The paper also provides a way to measure the surplus-value of joint production systems which overcomes the problems of the traditional concept and restates the proposition that a positive amount of surplus labour is a necessary condition for positive profits

Scaling and universality in the human voice

Speech is a distinctive complex feature of human capabilities. In order to understand the physics underlying speech production, in this work, we empirically analyse the statistics of large human speech datasets ranging several languages. We first show that during speech, the energy is unevenly released and powerlaw distributed, reporting a universal robust Gutenberg–Richter-like law in speech. We further show that such ‘earthquakes in speech’ show temporal correlations, as the interevent statistics are again power-law distributed. As this feature takes place in the intraphoneme range, we conjecture that the process responsible for this complex phenomenon is not cognitive, but it resides in the physiological (mechanical) mechanisms of speech production. Moreover, we show that these waiting time distributions are scale invariant under a renormalization group transformation, suggesting that the process of speech generation is indeed operating close to a critical point. These results are put in contrast with current paradigms in speech processing, which point towards low dimensional deterministic chaos as the origin of nonlinear traits in speech fluctuations. As these latter fluctuations are indeed the aspects that humanize synthetic speech, these findings may have an impact in future speech synthesis technologies. Results are robust and independent of the communication language or the number of speakers, pointing towards a universal pattern and yet another hint of complexity in human speech

Análisis regional de la pobreza para el colectivo de la Tercera Edad: inferencia clásica vs Técnicas Bootstrap

En este trabajo se analiza el perfil regional de la pobreza en los hogares encabezados por mayores de 65 años, un colectivo especialmente sensible a situarse por debajo del umbral de pobreza. Para ello, a partir de los datos del fichero longitudinal de la Encuesta Continua de Presupuestos Familiares del año 2002, realizada por el Instituto Nacional de Estadística, se estiman índices de la familia de Foster, Greer y Thorbecke que permiten estudiar la incidencia, intensidad y desigualdad de la pobreza. El objetivo de este trabajo es doble. Por un lado, se pretende obtener un mapa de la distribución regional de la pobreza para el colectivo de la tercera edad en España. Los resultados muestran que las comunidades autónomas con mayores niveles de pobreza son Castilla La Mancha, Extremadura y Andalucía. Por el contrario, las comunidades autónomas con menores niveles de pobreza son Navarra, Madrid y País Vasco. Por otro lado, se pretende comparar la precisión de las técnicas de inferencia clásicas con técnicas basadas en métodos computacionales. Para ello, se estiman los índices de pobreza mediante el cálculo de intervalos de confianza utilizando dos métodos alternativos. En primer lugar, se obtienen los intervalos mediante la determinación de distribuciones asintóticas. Posteriormente, se determinan los intervalos utilizando metodología del bootstrap percentil. La comparación de estos métodos de estimación muestra cómo para muestras pequeñas, las técnicas bootstrap permiten obtener resultados más adecuados

A opinião de jovens futebolistas sobre o envolvimento parental na sua prática desportiva

Objetivo: conhecer a opinião das crianças sobre o envolvimento parental. Metodologia: A amostra é constituída por 203 crianças praticantes de futebol, entre os escalões de infantis e iniciados. O instrumento utilizado foi o questionário adaptado do “Parental Involvement Sport Questionnaire” de Lee e Mclean (1997). Resultados: Na opinião das crianças há um grande envolvimento dos mesmos na prática desportiva dos filhos. Conclusões: estudo demonstrou que há diferenças na influência e intervenção e no incentivo e preocupação dos pais na prática desportiva dos filhos, entre os infantis e iniciados. Há também diferenças no incentivo e preocupação dos pais na prática desportiva dos filhos e no espírito desportivo, entre os pais que têm habilitações literárias altas e baixas. Há ainda diferenças na influência e intervenção dos pais na prática desportiva dos filhos e no incentivo e preocupação com essa prática, entre os pais com e sem prática desportiva.info:eu-repo/semantics/publishedVersio

Cinética da hidratação do aluminato tricálcico cúbico e ortorrômbico na primeira hora : estudo com fases cristalinas sintéticas e extraídas do clínquer Portland

Durante o processo de produção do clínquer Portland ocorrem fusões parciais da matéria prima e nódulos de clínquer de cimento Portland são produzidos. As características físico-químicas destes nódulos influenciam diretamente a cinética de hidratação do cimento, sendo a fase cristalina do aluminato tricálcico (C3A) uma das principais responsáveis pelas reações iniciais de hidratação. O C3A puro tem sua estrutura cristalina cúbica. A presença de elementos menores, principalmente o Na+, K+, Mg2+, Fe3+ e Si4+, derivado das matérias primas e/ou combustíveis, durante a clinquerização podem modificar a estrutura cristalina do C3A, em substituição aos íons Ca2+. Quando há incorporação destes íons em teores suficientes na estrutura cristalina do C3A, esta pode ser modificada de cúbica para ortorrômbica, sendo os compostos Na-C3A e K-C3A as principais e mais comumente fases polimórficas encontradas nas composições de clínqueres comerciais. A reação do C3A com a água é quase instantânea, com grande liberação de calor, caracterizando um processo exotérmico. O processo de liberação de calor é controlado com adição de uma fonte de sulfato de cálcio ao material, tendo como produto formado pela hidratação na reação com C3A, as fases trissulfoaluminato de cálcio hidratado (AFt ou etringita) e monossulfoaluminato de cálcio (AFm). Estudos apresentam resultados contraditórios quanto à influência dos tipos de estrutura cristalina do C3A durante o processo de hidratação, mediante o sistema C3A-Ca∙SO4-H2O. A influência de cada uma dessas estruturas é preferencialmente estudada de forma isolada, sendo estas produzidas sinteticamente, o que gera questionamentos quanto à validade destes resultados quando comparados à hidratação do cimento Portland, visto que as fases sintéticas produzidas em laboratório, diferentemente das encontrados no cimento, são puras. Apesar de todo conhecimento acumulado, ainda existem lacunas importantes a serem preenchidas quanto à hidratação das fases C3A na ausência ou na presença de sulfato de cálcio. Esta pesquisa visa utilizar fases de C3A sintéticas produzidas em laboratório e extraídas de clínqueres Portland (com diferentes teores de C3A cúbico e ortorrômbico) através da técnica de dissolução seletiva (DS), no estudo da hidratação na ausência e na presença de gipsita (CaSO4∙2H2O) e anidrita (CaSO4). Foram testados dois métodos de DS, sendo um deles adaptado após os resultados preliminares. A validação dos resultados exigiu uma gama de técnicas as quais, em associação, permitiram o avanço na pesquisa, tendo sido utilizada a Difração de Raios X (DRX), Fluorescência de Raios X (FRX) e espectroscopia RAMAN para tal objetivo. Os resultados indicaram a completa extração das fases aluminatos das amostras de clínquer Portland analisadas mediante modificação do processo com solução de ácido maleico/metanol (AMM). Os estudos de hidratação comprovaram uma maior reatividade do C3A cúbico na ausência de uma fonte de sulfato de cálcio, e na presença, a maior reatividade para C3A ortorrômbico até a primeira hora de hidratação, sendo que para as amostras sintéticas a presença da anidrita teve maior influência na reação de hidratação. Os resultados evidenciaram a eficiência das análises com uso de fases sintéticas, no entanto os dados experimentais comprovaram que as fases C3A extraídas apresentam maior reatividade, quando comparadas a fases sintéticas em condições similares. Entretanto, algumas fases do clínquer que não foram possíveis de ser extraídas, como periclásio e ferroaluminato, podem ter influenciado os resultados, o que indica o necessário aprimoramento da técnica de DS ou utilização de clínquer branco para esse método modificado.During clinker production partial fusions of the raw materials occurs and nodules of clinker are produced. The physicochemical characteristics of these nodules can directly influence the cement hydration kinetics, and the crystalline phase of tricalcium aluminate (C3A) is the main responsible for the initial hydration reactions. The pure C3A has cubic crystal structure. The presence of minor elements, mainly Na+, K+, Mg2+, Fe3+ and Si4+, derived from raw materials and/or fuels during clinkerization can modify the crystalline structure of C3A. When sufficient amount of these ions is incorporated into the C3A crystalline structure, it can be modified from cubic to orthorhombic. Na-C3A and K-C3A are the main polymorphs compounds and the most commonly found in the commercial clinker composition. The C3A reaction with water is almost instantaneous with large heat release featuring an exothermic process. The heat release is controlled adding a calcium sulphate source, the main hydrate products of the reaction are ettringite (AFt) and calcium monosulfate (AFm). Previous research shows conflicting results regarding the influence of the C3A crystalline structure types during the hydration in the C3A-Ca∙SO4-H2O system. The influence of each of these structures are rather studied using pure phases produced in laboratory, which leads to questions about the validity of these results against the real Portland cement phases hydration due to the high purity of these materials produced in laboratory. Despite all accumulated knowledge, there are still significant gaps to be filled about the hydration of C3A phases in the absence or presence of calcium sulfate sources. This research aims to study the hydration of C3A phases produced in laboratory and extracted from Portland clinkers using selective dissolution technique, in the absence and presence of gypsum (CaSO4 2H2O) and anhydrite (CaSO4). To elucidate the reactivity between the cubic and orthorhombic C3A phases, investigations will be carried out in clinkers with different amounts of cubic and orthorhombic C3A in their compositions. Two selective dissolution methods were tested and after previous results one of them was adapted. X ray diffraction (XRD), X ray fluorescence (XRF), isothermal calorimetry among other techniques were used. The results indicated the complete extraction of the aluminate phases of the Portland clinker samples. The hydration studies indicated higher reactivity for cubic C3A in the absence of calcium sulphate sources and for orthorhombic in presence of calcium sulphate sources in the first hour of hydration, in addition, for synthetic samples, the presence of anhydrite had a major influence on the hydration reaction. Results corroborate the efficiency in the use of synthetic phases for hydration tests, but the samples using the extracted aluminate phases showed higher reactivity. However, non-extracted phases such as periclase and C4AF may have influenced the results. Further studies are necessary to improve the DS method or the use of white Portland clinker in the dissolution

The Effects of Grants and the Marginal Cost of Public Funds: Evidence from Brazilian States

The flypaper effect is the empirical anomaly by which intergovernmental grants tend to be transformed by recipient authorities into public expenditures at a considerably higher rate than local private resources. The objective of this research is to detect the existence and investigate the causes of the flypaper effect in the Brazilian states. Panel data evidence from 27 Brazilian states from 1985 to 2010 indicates the existence of a large flypaper effect, with an estimated impact of grants on public expenditures. Considering there are some ways to calculate MCF proxies, first, an autonomous index was used as a proxy of the marginal cost of public funds (MCF), because it represents how much the municipality can survive by itself, representing the municipalities’ independency to federal grants. Second, the MCF was calculated by the derivation of Proper Tax Revenue to the Total Revenues. The results show that the stimulative effect of grants on public spending increases with the MCF in both proxies, but it was stronger in the autonomous index proxy, in convergence to results of [5] to Canadian provincial data

Phase transitions in number theory: from the birthday problem to Sidon sets

In this work, we show how number theoretical problems can be fruitfully approached with the tools of statistical physics. We focus on g-Sidon sets, which describe sequences of integers whose pairwise sums are different, and propose a random decision problem which addresses the probability of a random set of k integers to be g-Sidon. First, we provide numerical evidence showing that there is a crossover between satisfiable and unsatisfiable phases which converts to an abrupt phase transition in a properly defined thermodynamic limit. Initially assuming independence, we then develop a mean-field theory for the g-Sidon decision problem. We further improve the mean-field theory, which is only qualitatively correct, by incorporating deviations from independence, yielding results in good quantitative agreement with the numerics for both finite systems and in the thermodynamic limit. Connections between the generalized birthday problem in probability theory, the number theory of Sidon sets and the properties of q-Potts models in condensed matter physics are briefly discusse

Proyecto de titulación producción musical y sonido

La idea conceptual del proyecto se basa en el existencialismo, en como la incomprensión de la muerte se manifiesta a través del dolor en las personas, y de cómo en realidad el significado de la muerte es algo ajeno hasta que se lo experimenta. Por lo tanto, la idea de una lápida sin epitafio (No Epitaph), invita al público a cuestionarse sobre uno mismo, el valor de su vida, sus acciones y consecuencias. Es por esto que, tanto la agrupación como el material de promoción se llamaran No Epitaph. Por otro lado, musicalmente hablando, el proyecto se desenvuelve mediante la brutalidad y complejidad rítmica y técnica del death metal con arr glos y progr sion s armónicas “oscuras” qu s an cons cu nt s al concepto. De la misma forma, el death metal al haber sido desarrollado en los Estados Unido de América y por mantener la estética del género, las letras de los temas son en inglés

Influence of Pre-Turbine Small-Sized Oxidation Catalyst on Engine Performance and Emissions under Driving Conditions

[EN] The earlier activation of the catalytic converters in internal combustion engines is becoming highly challenging due to the reduction in exhaust gas temperature caused by the application of CO2 reduction technologies. In this context, the use of pre-turbine catalysts arises as a potential way to increase the conversion efficiency of the exhaust aftertreatment system. In this work, a small-sized oxidation catalyst consisting of a honeycomb thin-wall metallic substrate was placed upstream of the turbine to benefit from the higher temperature and pressure prior to the turbine expansion. The change in engine performance and emissions in comparison to the baseline configuration are analyzed under driving conditions. As an individual element, the pre-turbine catalyst contributed positively with a relevant increase in the overall CO and HC conversion efficiency. However, its placement produced secondary effects on the engine and baseline aftertreatment response. Although small-sized monoliths are advantageous to minimize the thermal inertia impact on the turbocharger lag, the catalyst cross-section is in trade-off with the additional pressure drop that the monolith causes. As a result, the higher exhaust manifold pressure in pre-turbine pre-catalyst configuration caused a fuel consumption increase higher than 3% while the engine-out CO and HC emissions did around 50%. These increments were not completely offset despite the high pre-turbine pre-catalyst conversion efficiency (>40%) because the partial abatement of the emissions in this device conditioned the performance of the close-coupled oxidation catalyst.This research has been partially supported by FEDER and the Government of Spain through project TRA2016-79185-R and by Universitat Politecnica de Valencia under a grant with reference number FPI-2018-S2-10 to the Ph.D. student Maria Jose Ruiz.Serrano, J.; Piqueras, P.; De La Morena, J.; Ruiz-Lucas, MJ. (2020). Influence of Pre-Turbine Small-Sized Oxidation Catalyst on Engine Performance and Emissions under Driving Conditions. Applied Sciences. 10(21):1-17. https://doi.org/10.3390/app10217714S1171021Serrano, J. R., Novella, R., & Piqueras, P. (2019). Why the Development of Internal Combustion Engines Is Still Necessary to Fight against Global Climate Change from the Perspective of Transportation. Applied Sciences, 9(21), 4597. doi:10.3390/app9214597Road Transport: Reducing CO2 Emissions from Vehicles. European Commissionhttps://ec.europa.eu/clima/policies/transport/vehicles/carsJoshi, A. (2020). Review of Vehicle Engine Efficiency and Emissions. SAE Technical Paper Series. doi:10.4271/2020-01-0352Gohil, D. B., Pesyridis, A., & Serrano, J. R. (2020). Overview of Clean Automotive Thermal Propulsion Options for India to 2030. Applied Sciences, 10(10), 3604. doi:10.3390/app10103604Jain, A., Krishnasamy, A., & V, P. (2020). Computational optimization of reactivity controlled compression ignition combustion to achieve high efficiency and clean combustion. International Journal of Engine Research, 22(7), 2213-2232. doi:10.1177/1468087420931730Claßen, J., Pischinger, S., Krysmon, S., Sterlepper, S., Dorscheidt, F., Doucet, M., … Thewes, S. C. (2020). Statistically supported real driving emission calibration: Using cycle generation to provide vehicle-specific and statistically representative test scenarios for Euro 7. International Journal of Engine Research, 21(10), 1783-1799. doi:10.1177/1468087420935221Di Maio, D., Beatrice, C., Fraioli, V., Napolitano, P., Golini, S., & Rutigliano, F. G. (2019). Modeling of Three-Way Catalyst Dynamics for a Compressed Natural Gas Engine during Lean–Rich Transitions. Applied Sciences, 9(21), 4610. doi:10.3390/app9214610Reitz, R. D., Ogawa, H., Payri, R., Fansler, T., Kokjohn, S., Moriyoshi, Y., … Zhao, H. (2019). IJER editorial: The future of the internal combustion engine. International Journal of Engine Research, 21(1), 3-10. doi:10.1177/1468087419877990Kawaguchi, A., Wakisaka, Y., Nishikawa, N., Kosaka, H., Yamashita, H., Yamashita, C., … Tomoda, T. (2019). Thermo-swing insulation to reduce heat loss from the combustion chamber wall of a diesel engine. International Journal of Engine Research, 20(7), 805-816. doi:10.1177/1468087419852013Luján, J. M., Serrano, J. R., Piqueras, P., & Diesel, B. (2019). Turbine and exhaust ports thermal insulation impact on the engine efficiency and aftertreatment inlet temperature. Applied Energy, 240, 409-423. doi:10.1016/j.apenergy.2019.02.043Arnau, F. J., Martín, J., Pla, B., & Auñón, Á. (2020). Diesel engine optimization and exhaust thermal management by means of variable valve train strategies. International Journal of Engine Research, 22(4), 1196-1213. doi:10.1177/1468087419894804Maniatis, P., Wagner, U., & Koch, T. (2018). A model-based and experimental approach for the determination of suitable variable valve timings for cold start in partial load operation of a passenger car single-cylinder diesel engine. International Journal of Engine Research, 20(1), 141-154. doi:10.1177/1468087418817119Luján, J. M., Bermúdez, V., Piqueras, P., & García-Afonso, Ó. (2015). Experimental assessment of pre-turbo aftertreatment configurations in a single stage turbocharged diesel engine. Part 1: Steady-state operation. Energy, 80, 599-613. doi:10.1016/j.energy.2014.05.048Luján, J. M., Serrano, J. R., Piqueras, P., & García-Afonso, Ó. (2015). Experimental assessment of a pre-turbo aftertreatment configuration in a single stage turbocharged diesel engine. Part 2: Transient operation. Energy, 80, 614-627. doi:10.1016/j.energy.2014.12.017Serrano, J. R., Climent, H., Piqueras, P., & Angiolini, E. (2014). Analysis of fluid-dynamic guidelines in diesel particulate filter sizing for fuel consumption reduction in post-turbo and pre-turbo placement. Applied Energy, 132, 507-523. doi:10.1016/j.apenergy.2014.07.043Joergl, V., Keller, P., Weber, O., Mueller-Haas, K., & Konieczny, R. (2008). Influence of Pre Turbo Catalyst Design on Diesel Engine Performance, Emissions and Fuel Economy. SAE International Journal of Fuels and Lubricants, 1(1), 82-95. doi:10.4271/2008-01-0071Serrano, J. R., Bermúdez, V., Piqueras, P., & Angiolini, E. (2017). On the impact of DPF downsizing and cellular geometry on filtration efficiency in pre- and post-turbine placement. Journal of Aerosol Science, 113, 20-35. doi:10.1016/j.jaerosci.2017.07.014Kröcher, O., Elsener, M., Bothien, M.-R., & Dölling, W. (2014). Pre-Turbo Scr - Influence of Pressure on NOx Reduction. MTZ worldwide, 75(4), 46-51. doi:10.1007/s38313-014-0140-xBermúdez, V., Serrano, J. R., Piqueras, P., & García-Afonso, O. (2011). Assessment by means of gas dynamic modelling of a pre-turbo diesel particulate filter configuration in a turbocharged HSDI diesel engine under full-load transient operation. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 225(9), 1134-1155. doi:10.1177/0954407011402278Payri, F., Serrano, J. R., Piqueras, P., & García-Afonso, O. (2011). Performance Analysis of a Turbocharged Heavy Duty Diesel Engine with a Pre-turbo Diesel Particulate Filter Configuration. SAE International Journal of Engines, 4(2), 2559-2575. doi:10.4271/2011-37-0004Serrano, J. R., Guardiola, C., Piqueras, P., & Angiolini, E. (2014). Analysis of the Aftertreatment Sizing for Pre-Turbo DPF and DOC Exhaust Line Configurations. SAE Technical Paper Series. doi:10.4271/2014-01-1498Klaewkla, R., Arend, M., & F., W. (2011). A Review of Mass Transfer Controlling the Reaction Rate in Heterogeneous Catalytic Systems. Mass Transfer - Advanced Aspects. doi:10.5772/22962Piqueras, P., García, A., Monsalve-Serrano, J., & Ruiz, M. J. (2019). Performance of a diesel oxidation catalyst under diesel-gasoline reactivity controlled compression ignition combustion conditions. Energy Conversion and Management, 196, 18-31. doi:10.1016/j.enconman.2019.05.111Sampara, C. S., Bissett, E. J., & Chmielewski, M. (2007). Global Kinetics for a Commercial Diesel Oxidation Catalyst with Two Exhaust Hydrocarbons. Industrial & Engineering Chemistry Research, 47(2), 311-322. doi:10.1021/ie070813

Biodiversity patterns of macroinvertebrate assemblages in natural and artificial lentic waters on an Oceanic Island

The Azorean islands have been historically affected by human activities, mainly due to the combined effects of habitat degradation and fragmentation, and the introduction of exotic species. We here aim to analyze the role of environmental characteristics and spatial descriptors in supporting regional biodiversity of macroinvertebrates by considering natural ponds and artificial tanks. After the monthly variation of macroinvertebrate assemblages was assessed in three temporary and two permanent ponds in the Azorean island of Terceira during a complete inundation-desiccation annual cycle, the assemblage differences of 12 ponds (three temporary and nine permanent ponds) and 8 closely-located artificial tanks were analyzed across a range of landscape disturbances. Macroinvertebrate assemblages were found to differ according to hydroperiod and sampled months. Although the former explained the highest variance, macroinvertebrate differentiation by hydroperiod was also dependent on the study month. Our results also revealed a consistent monthly pattern of species replacement. However, the contribution of nestedness to the macroinvertebrate β-diversity was notable when temporary ponds were close to desiccation, probably indicating a deterministic loss of species due to the impoverished water conditions of the ponds facing desiccation. When the macroinvertebrate assemblages were analyzed in relation to physico-chemical variations and spatial descriptors, the artificial tanks were not clearly segregated from the natural ponds, and only differentiated by pH differences. In contrast, those natural ponds exhibiting high concentrations of total phosphorous (likely signs of anthropization) also discriminated the ordination of ponds in a distance-based redundancy analysis, and showed impoverished assemblages in comparison with well-preserved ponds. The macroinvertebrate assemblages of the natural ponds showed a significant spatial pattern, but this spatial influence was not significant when tanks and ponds were considered together. Our results suggest that tanks may act as possible reservoirs of biodiversity during the desiccation period of temporary ponds, but are unable to establish successful populations. These fishless permanent tanks can complement the conservation of a biodiversity that is largely maintained by the pristine high-altitude natural ponds. The establishment of a guideline for conservation management that also considers the artificial tanks is necessary to benefit the local and regional Azorean macroinvertebrate diversit