Relative roles of instruction count and cycles per instruction in WCET estimation

Most of the existing WCET estimation methods directly estimate execution time, ET, in cycles. We propose to study ET as a product of two factors, ET = IC * CPI, where IC is instruction count and CPI is cycles per instruction. Considering directly the estimation of ET may lead to a highly pessimistic estimate since implicitly these methods may be using worst case IC and worst case CPI. We hypothesize that there exists a functional relationship between CPI and IC such that CPI=f(IC). This is ascertained by computing the covariance matrix and studying the scatter plots of CPI versus IC. IC and CPI values are obtained by running benchmarks with a large number of inputs using the cycle accurate architectural simulator, Simplescalar on two different architectures. It is shown that the benchmarks can be grouped into different classes based on the CPI versus IC relationship. For some benchmarks like FFT, FIR etc., both IC and CPI are almost a constant irrespective of the input. There are other benchmarks that exhibit a direct or an inverse relationship between CPI and IC. In such a case, one can predict CPI for a given IC as CPI=f(IC). We derive the theoretical worst case IC for a program, denoted as SWIC, using integer linear programming(ILP) and estimate WCET as SWIC*f(SWIC). However, if CPI decreases sharply with IC then measured maximum cycles is observed to be a better estimate. For certain other benchmarks, it is observed that the CPI versus IC relationship is either random or CPI remains constant with varying IC. In such cases, WCET is estimated as the product of SWIC and measured maximum CPI. It is observed that use of the proposed method results in tighter WCET estimates than Chronos, a static WCET analyzer, for most benchmarks for the two architectures considered in this paper.

Ratiometric, reversible, and parts per billion level detection of multiple toxic transition metal ions using a single probe in micellar media

We present the selective sensing of multiple transition metal ions in water using a synthetic single probe. The probe is made up of pyrene and pyridine as signaling and interacting moiety, respectively. The sensor showed different responses toward metal ions just by varying the medium of detection. In organic solvent (acetonitrile), the probe showed selective detection of Hg2+ ion. In water, the fluorescence quenching was observed with three metal ions, Cu2+, Hg2+, and Ni2+. Further, just by varying the surface charge on the micellar aggregates, the probe could detect and discriminate the above-mentioned three different toxic metal ions appropriately. In neutral micelles (Brij 58), the probe showed a selective interaction with Hg2+ ion as observed in acetonitrile medium. However, in anionic micellar medium (sodium dodecyl sulfate, SDS), the probe showed changes with both Cu2+ and Ni2+. under UV-vis absorption spectroscopy. The discrimination between these two ions was achieved by recording their emission spectra, where it showed selective quenching with Cu2+.

An Efficient Probe for Rapid Detection of Cyanide in Water at Parts per Billion Levels and Naked-Eye Detection of Endogenous Cyanide

A new molecular probe based on an oxidized bis-indolyl skeleton has been developed for rapid and sensitive visual detection of cyanide ions in water and also for the detection of endogenously bound cyanide. The probe allows the naked-eye detection of cyanide ions in water with a visual color change from red to yellow ((max)=80nm) with the immediate addition of the probe. It shows high selectivity towards the cyanide ion without any interference from other anions. The detection of cyanide by the probe is ratiometric, thus making the detection quantitative. A Michael-type addition reaction of the probe with the cyanide ion takes place during this chemodosimetric process. In water, the detection limit was found to be at the parts per million level, which improved drastically when a neutral micellar medium was employed, and it showed a parts-per-billion-level detection, which is even 25-fold lower than the permitted limits of cyanide in water. The probe could also efficiently detect the endogenously bound cyanide in cassava (a staple food) with a clear visual color change without requiring any sample pretreatment and/or any special reaction conditions such as pH or temperature. Thus the probe could serve as a practical naked-eye probe for in-field experiments without requiring any sophisticated instruments.

A Probe for the Selective and Parts-per-Billion-Level Detection of Copper(II) and Mercury(II) using a Micellar Medium and Its Utility in Cell Imaging

A novel colorimetric probe 1 based on the picolyl moiety has been designed and synthesized. Probe 1 is composed of a pyrene and a bispicolyl amine (BPA) unit, in which the BPA moiety acts as a binding unit and the binding phenomenon is sensed from the changes in the signaling subunit. The probe detects Cu2+ specifically in water and both Cu2+ and Hg2+ efficiently in neutral Brij-58 micellar media. The probe shows a color change visible to the naked eye upon addition of metal ions. Notably, in a micellar medium, probe 1 can detect both the Cu2+ and Hg2+ ions even at parts-per-billion levels. Furthermore, the probe shows ratiometric detection of both the metal ions making the sensing quantitative. The two metal ions could be discriminated both visibly under a UV lamp and with the use of fluorescence spectroscopy. The probe could be also used in biological cell lines for the detection of both Hg2+ and Cu2+ ions.

A critical review of the definition of FRA resonance frequency of transformers as per IEEE Std C57.149-2012

The explanation of resonance given in IEEE Std C57.149-2012 to define resonance during frequency response analysis (FRA) measurements on transformers implicitly uses the conditions prevalent during resonance in a series R-L-C circuit. This dependence is evident from the two assertions made in the definition, viz., resulting in zero net reactive impedance, and, accompanied by a zero value appearing in the phase angle of the frequency response function. These two conditions are satisfied (at resonance) only in a series R-L-C circuit and certainly not in a transformer, as has been assumed in the Standard. This can be proved by considering a ladder-network model. Circuit analysis of this ladder network reveals the origin of this fallacy and proves that, at resonance, neither is the ladder network purely resistive and nor is the phase angle (between input voltage and input current) always zero. Also, during FRA measurements, it is often seen that phase angle does not traverse the conventional cyclic path from +90 degrees to -90 degrees (or vice versa) at all resonant frequencies. This peculiar feature can also be explained using pole-zero maps. Simple derivations, simulations and experimental results on an actual winding are presented. In summary, authors believe that this study dispels existing misconceptions about definition of FRA resonance and provides material for its correction in IEEE Std C57.149-2012. (C) 2014 Elsevier B.V. All rights reserved.

Training-Based Antenna Selection for PER Minimization: A POMDP Approach

This paper considers the problem of receive antenna selection (AS) in a multiple-antenna communication system having a single radio-frequency (RF) chain. The AS decisions are based on noisy channel estimates obtained using known pilot symbols embedded in the data packets. The goal here is to minimize the average packet error rate (PER) by exploiting the known temporal correlation of the channel. As the underlying channels are only partially observed using the pilot symbols, the problem of AS for PER minimization is cast into a partially observable Markov decision process (POMDP) framework. Under mild assumptions, the optimality of a myopic policy is established for the two-state channel case. Moreover, two heuristic AS schemes are proposed based on a weighted combination of the estimated channel states on the different antennas. These schemes utilize the continuous valued received pilot symbols to make the AS decisions, and are shown to offer performance comparable to the POMDP approach, which requires one to quantize the channel and observations to a finite set of states. The performance improvement offered by the POMDP solution and the proposed heuristic solutions relative to existing AS training-based approaches is illustrated using Monte Carlo simulations.

El impacto de la Primera Invasión Inglesa a la Ciudad de Buenos Aires en 1806, en la política del virrey José Fernando de Abascal y Sousa para el Virreinato del Perú

Resumen: José Fernando de Abascal y Sousa recibió la noticia de la invasión inglesa de 1806 a Buenos Aires, en el inicio de su administración como virrey del Virreinato del Perú. A partir de esta primera misiva enviada por el virrey Rafael de Sobre Monte, comenzó un intercambio epistolar entre las dos autoridades sobre dicho acontecimiento, a partir del cual se fueron perfi lando las preocupaciones, cuidados y políticas iniciales de defensa aplicadas por Abascal a su jurisdicción.

Reforma y contra reforma comercial en América Latina : Perú y Argentina

"Bajo democracia, durante los ‘90 Perú y Argentina abrieron sus economías como una de las políticas que los sacarían de décadas de decadencia relativa. Esta liberalización fue unilateral pero ambos países consolidaron sus reformas con obligaciones que asumieron en el GATT/OMC. Argentina además se asoció al Mercosur implementando un arancel externo común altamente coincidente con los valores establecidos unilateralmente..."

El sentimiento partidista presente en el inicio de la Conquista del Perú : supervivencia medieval en los conflictos entre Pizarro y Almagro

El siglo XVI americano fue escenario de la lucha de partidos entre los españoles que defendieron con vigorosa fidelidad a sus respectivos líderes. En la Conquista del Perú se encuentra el caso que mejor demuestra el nivel de violencia que alcanzaron las rivalidades partidarias. Fue en la singular, difícil y posteriormente violenta relación entre Diego de Almagro y Francisco Pizarro desde la salida de Panamá en 1524 hasta la lucha por la dominación de la ciudad del Cuzco en 1538.

Repertorio dos cinquo livros das Ordenações do Senhor Rey D. Manuel, com addições das leys extravagantes : dirigido ao muito Illustre Senhor Dom Francisco Coutinho, Conde do Redondo, regedor da justiça deste reino / per o licenciado Duarte Nunez do Lião, Procurador da Casa da Soppricação

As ‘Ordenaçoens do Senhor Rey D. Manuel’, conhecidas como Manuelinas, foram promulgadas, pela primeira vez, em 1514. Posteriormente, o rei mandou que esta edição fosse destruída, sendo substituída pela segunda e definitiva edição de 1521. Esta edição diferencia-se da primeira pela inclusão de muitas outras leis e ordenações pelo número de títulos, pela substância da legislação, pela ordem e disposição das matérias e pelo prólogo. O trabalho de organização deveu-se ao Chanceler-Mor Rui de Grã e ao Desembargador Cristóvão Esteves, principalmente. Em seu plano geral, as novas ‘Ordenaçoens’, embora redigidas em estilo mais conciso e decretatório, seguem o ‘Código Afonsino’, seu predecessor. Divergem desse código apenas na omissão de certas disposições que, na época, já haviam caducado e na introdução de outras providências adotadas no decurso dos sessenta anos de intervalo entre as duas compilações. Em 1560, Duarte Nunes do Leão organizou e dirigiu a elaboração do ‘Repertório dos cinquo livros das Ordenações do Senhor Rey D. Manuel, com addições das leys extravagantes’, complementando a coleção já existente

O Brasil e o mundo em dados comparativos : os continentes, os países, o Brasil, as regiões, os estados e os municípios comparados em valores absolutos, relativos e per capita

Trata-se de uma enciclopédia de estatísticas entre os três níveis de governo: desde educação, saúde, desenvolvimento humano, passando por estatísticas de produção agropecuária até chegar a assuntos tributários. Apresenta também dados estatísticos comparativos referentes aos continentes.

Leis extravagantes / Collegidas e Relatadas pelo Licenciado Duarte Nunez do Lião ; per mandado do muito alto e muito poderoso rei Dom Sebastião, Nosso Senhor

As Leis extravagantes foram compiladas durante o reinado de D.Sebastião. Levada a efeito com o intuito de reformar o código precedente, servia para consumar o triunfo da legislação Corpus Juris e do absolutismo real, conforme analisa Cândido Mendes. Essa nova codificação, também denominada Código Sebastiânico, contudo, não teve o alcance das Leis extravagantes posteriores ao Código manuelino. O trabalho, revisto pelo regedor Lourenço da Silva e outros jurisconsultos, foi aprovado por alvará de 14 de fevereiro de 1569, tendo força de lei. Foi o Cardeal D. Henrique, quando regente do Reino, que ordenara a compilação, alegando a existência de muitas leis e provisões promulgadas depois do Código manuelino, assim como decisões da Casa da Suplicação, o que era fonte de muita controvérsia no fórum, como é declarado no alvará contido na obra. O livro das Leis extravagantes resultou num grosso volume de oitocentas e oitenta páginas, mais quatorze páginas introdutórias, em que aparecem o licenciamento e o sumário da obra. O conteúdo das Leis extravagantes é constituído por seis partes, seus aditamentos, o repertório das matéria contidas na obra, as anotações dos dispositivos revogados e casos de devassa.