Non-parametric segmentation of non-stationary time series

The non-stationary evolution of observable quantities in complex systems can frequently be described as a juxtaposition of quasi-stationary spells. Given that standard theoretical and data analysis approaches usually rely on the assumption of stationarity, it is important to detect in real time series intervals holding that property. With that aim, we introduce a segmentation algorithm based on a fully non-parametric approach. We illustrate its applicability through the analysis of real time series presenting diverse degrees of non-stationarity, thus showing that this segmentation procedure generalizes and allows to uncover features unresolved by previous proposals based on the discrepancy of low order statistical moments only

Essence and Cause: Making Something Be What It Is

Aristotle frequently describes essence as a “cause” or “explanation”, thus ascribing to essence some sort of causal or explanatory role. This explanatory role is often explicated by scholars in terms of essence “making the thing be what it is” or “making it the very thing that it is”. I argue that this is problematic, at least on the assumption that “making” expresses an explanatory relation, since it violates certain formal features of explanation. I then consider whether Aristotle is vulnerable to this problem by examining the explanatory role of essence in Posterior Analytics and Metaphysics Z 17

Design of a Broadband Amplifier for High Speed Applications

This paper provides comprehensive insight into the design approach followed for an amplifier dedicated to high speed base band signals. To demonstrate the methodology, an amplifier consisting of nine PHEMT cascode cells within a distributed amplifier topology was designed. The resulting frequency response is 40 GHz at the 3-dB point, and the output voltage for a 43 Gbps eye diagram is 7.3 Vpp at the chip terminal

Os discursos de licenciandos, professores universitários e secundários contribuindo para a reestruturação curricular de um curso de licenciatura em Física

Este estudo foca-se na reestruturação curricular de um curso de licenciatura em Física de uma universidade pública. No processo foram analisados, discursos de licenciandos, docentes universitários e professores em exercício procurando-se entender como as demandas desses grupos influenciaram na estrutura curricular resultante. Para interpretar os efeitos de sentidos presentes em documentos e discursos dos sujeitos envolvidos foram adotados referenciais teórico-metodológicos embasados em teorias críticas e na Análise de Discurso de linha francesa. A proposta final situou-se entre as exigências legais e a realidade acadêmica. A legislação consultada, os professores em exercício, os licenciandos e os formadores na Universidade, subsidiaram ou sinalizaram o que e como a estrutura curricular do Curso poderia ter ou ser alterada

A 43-Gbps Lithium Niobate Modulator Driver Module

This paper describes the realization of a 43-Gbps Lithium Niobate modulator driver module. The NRZ driver module utilizes four stages of GaAs p-HEMT MMIC amplifiers integrated with an output level detector and feedback loop to provide thermal stability and external control of the output swing. The bias and loop control circuitry are contained in the housing on a PC board external to the sealed MIC section. The integrated module (50.8 x 73.4 x 9.5 mm 3) provides 6.0 Vp-p controllable single-ended output voltage while dissipating only 4 watt

National input-output table of Brazil

This paper reports on the basic information about the Brazilian input-output tables. First part presents the history of constructing I-O tables in Brazil, starting from the non-official table of 1959. The second part illustrates some basic features of the last table with the reference year of 2005. It also articulates the issues concerning the integration of the table into 2005 BRICS International Input-Output Table.Brazil; Input-Output; Tables

Employment generation in Brazilian coffee regions

Due to the specific characteristics of coffee production on each of the main Brazilian states producers of arabica (Coffea arabica) and robusta coffee (Coffea canephora), a better understanding of the structural links between production and industrialization of coffee on those states and the national economy can provide subsides for implementation of public policies, essential to plan the coffee production and increase the sector competitiveness. Therefore, this study analyzed the employment generation in production and coffee industrialization in the major Brazilian production regions, based on an inter-regional input-output model, with seven regions, which represent the main coffee-producing states - Minas Gerais, Espirito Santo, São Paulo, Paraná, Bahia and Other States - with 44 sectors each, in a system of 308 sectors. The results indicated that the production of robusta coffee is the sector that generates more employments (total) per currency unit, and that arabica production sector is the fourth largest generator of employments, among the 44 sectors considered for the country. The results for each state emphasized the importance of farming and coffee industry for national and state economies.Coffee; Coffee Production; Input-Output