Improvement of link failure restoration utilising multi-protocol label switching (MPLS) as a means to maintain quality of service (QOS)

This paper proposes a practical approach to the enhancement of Quality of Service (QoS) routing by means of providing alternative or repair paths in the event of a breakage of a working path. The proposed scheme guarantees that every Protected Node (PN) is connected to a multi-repair path such that no further failure or breakage of single or double repair paths can cause any simultaneous loss of connectivity between an ingress node and an egress node. Links to be protected in an MPLS network are predefined and a Label Switched path (LSP) request involves the establishment of a working path. The use of multi-protection paths permits the formation of numerous protection paths allowing greater flexibility. Our analysis examined several methods including single, double and multi-repair routes and the prioritization of signals along the protected paths to improve the Quality of Service (QoS), throughput, reduce the cost of the protection path placement, delay, congestion and collision. Results obtained indicated that creating multi-repair paths and prioritizing packets reduces delay and increases throughput in which case the delays at the ingress/egress LSPs were low compared to when the signals had not been classified. Therefore the proposed scheme provided a means to improve the QoS in path restoration in MPLS using available network resources. Prioritizing the packets in the data plane has revealed that the amount of traffic transmitted using a medium and low priority Label Switch Paths (LSPs) does not have any impact on the explicit rate of the high priority LSP in which case the problem of a knock-on effect is eliminated.

Parkinson’s Disease tremor classification – a comparison between Support Vector Machines and neural networks

Deep Brain Stimulation has been used in the study of and for treating Parkinson’s Disease (PD) tremor symptoms since the 1980s. In the research reported here we have carried out a comparative analysis to classify tremor onset based on intraoperative microelectrode recordings of a PD patient’s brain Local Field Potential (LFP) signals. In particular, we compared the performance of a Support Vector Machine (SVM) with two well known artificial neural network classifiers, namely a Multiple Layer Perceptron (MLP) and a Radial Basis Function Network (RBN). The results show that in this study, using specifically PD data, the SVM provided an overall better classification rate achieving an accuracy of 81% recognition.

Rheology of discrete failure regimes of anisotropic sea ice

A rheological model of sea ice is presented that incorporates the orientational distribution of ice thickness in leads embedded in isotropic floe ice. Sea ice internal stress is determined by coulombic, ridging and tensile failure at orientations where corresponding failure criteria are satisfied at minimum stresses. Because sea ice traction increases in thinner leads and cohesion is finite, such failure line angles are determined by the orientational distribution of sea ice thickness relative to the imposed stresses. In contrast to the isotropic case, sea ice thickness anisotropy results in these failure lines becoming dependent on the stress magnitude. Although generally a given failure criteria type can be satisfied at many directions, only two at most are considered. The strain rate is determined by shearing along slip lines accompanied by dilatancy and closing or opening across orientations affected by ridging or tensile failure. The rheology is illustrated by a yield curve determined by combining coulombic and ridging failure for the case of two pairs of isotropically formed leads of different thicknesses rotated with regard to each other, which models two events of coulombic failure followed by dilatancy and refreezing. The yield curve consists of linear segments describing coulombic and ridging yield as failure switches from one lead to another as the stress grows. Because sliding along slip lines is accompanied by dilatancy, at typical Arctic sea ice deformation rates a one-day-long deformation event produces enough open water that these freshly formed slip lines are preferential places of ridging failure.

Bicorrelations and cross-bicorrelations as non-linearity tests and tools for exchange rate forecasting

This paper proposes and implements a new methodology for forecasting time series, based on bicorrelations and cross-bicorrelations. It is shown that the forecasting technique arises as a natural extension of, and as a complement to, existing univariate and multivariate non-linearity tests. The formulations are essentially modified autoregressive or vector autoregressive models respectively, which can be estimated using ordinary least squares. The techniques are applied to a set of high-frequency exchange rate returns, and their out-of-sample forecasting performance is compared to that of other time series models

Influence of pulse repetition rate of Er : YAG laser and dentin depth on tensile bond strength of dentin-resin interface

The study evaluated the in vitro influence of pulse-repetition rate of Er:YAG laser and dentin depth on tensile bond strength of dentin-resin interface. Dentin surfaces of buccal or lingual surfaces from human third molars were submitted to tensile test in different depths (superficial, 1.0 and 1.5 mm) of the same dental area, using the same sample. Surface treatments were acid conditioning solely (control) and Er:YAG laser irradiation (80 mJ) followed by acid conditioning, with different pulse-repetition rates (1, 2, 3, or 4 Hz). Single bond/Z-250 system was used. The samples were stored in distilled water at 37 degrees C for 24 h, and then the first test (superficial dentine) was performed. The bond failures were analyzed. Following, the specimens were identified, grounded until 1.0- and 1.5-mm depths, submitted again to the treatments and to the second and, after that, to third-bond tests on a similar procedure and failure analysis. ANOVA and Tukey test demonstrated a significant difference (p < 0.001) for treatment and treatment X depth interaction (p < 0.05). The tested depths did not show influence (p > 0.05) on the bond strength of dentin-resin interface. It may be concluded that Er:YAG laser with 1, 2, 3, or 4 Hz combined with acid conditioning did not increase the resin tensile bond strength to dentin, regardless of dentin depth. (C) 2007 Wiley Periodicals, Inc.

Density and survival rate of Culex quinquefasciatus at Parque Ecologico do Tiete, Sao Paulo, Brazil

Parity rate, gonotrophic cycle length, and density of a Culex quinquefasciatus female population was estimated at the Parque Ecologico do Tiete (PET), Sao Paulo, Brazil. Adult Cx. quinquefasciatus females were collected from vegetation along the edges of a polluted drainage canal with the use of a battery-powered backpack aspirator from September to November 2005 and from February to April 2006. We examined 255 Cx. quinquefasciatus ovaries to establish the parity rate of 0.22 and determined the gonotrophic cycle length under laboratory conditions to be 3 and 4 days. From these data, we calculated the Cx. quinquefasciatus survival rate to be 0.60 and 0.68 per day. Density of the Cx. quinquefasciatus female (5.71 females per m(2)) was estimated based on a population size of 28,810 individuals divided by the sampled area of 5,040 m(2). Results of all experiments indicate medium survivorship and high density of the Cx. quinquefasciatus female population. This species is epidemiologically relevant in the PET area and should be a target of the vector control program of Sao Paulo municipality.

Improved voice activity detection algorithm using wavelet and support vector machine

This paper proposes an improved voice activity detection (VAD) algorithm using wavelet and support vector machine (SVM) for European Telecommunication Standards Institution (ETS1) adaptive multi-rate (AMR) narrow-band (NB) and wide-band (WB) speech codecs. First, based on the wavelet transform, the original IIR filter bank and pitch/tone detector are implemented, respectively, via the wavelet filter bank and the wavelet-based pitch/tone detection algorithm. The wavelet filter bank can divide input speech signal into several frequency bands so that the signal power level at each sub-band can be calculated. In addition, the background noise level can be estimated in each sub-band by using the wavelet de-noising method. The wavelet filter bank is also derived to detect correlated complex signals like music. Then the proposed algorithm can apply SVM to train an optimized non-linear VAD decision rule involving the sub-band power, noise level, pitch period, tone flag, and complex signals warning flag of input speech signals. By the use of the trained SVM, the proposed VAD algorithm can produce more accurate detection results. Various experimental results carried out from the Aurora speech database with different noise conditions show that the proposed algorithm gives considerable VAD performances superior to the AMR-NB VAD Options 1 and 2, and AMR-WB VAD. (C) 2009 Elsevier Ltd. All rights reserved.

History of hypertension and eplerenone in patients with acute myocardial infarction complicated by heart failure

In the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study ( n = 6632), eplerenone- associated reduction in all- cause mortality was significantly greater in those with a history of hypertension ( Hx- HTN). There were 4007 patients with Hx- HTN ( eplerenone: n = 1983) and 2625 patients without Hx- HTN ( eplerenone: n = 1336). Propensity scores for eplerenone use, separately calculated for patients with and without Hx- HTN, were used to assemble matched cohorts of 1838 and 1176 pairs of patients. In patients with Hx- HTN, all- cause mortality occurred in 18% of patients treated with placebo ( rate, 1430/ 10 000 person- years) and 14% of patients treated with eplerenone ( rate, 1058/ 10 000 person- years) during 2350 and 2457 years of follow- up, respectively ( hazard ratio [ HR]: 0.71; 95% CI: 0.59 to 0.85; P < 0.0001). Composite end point of cardiovascular hospitalization or cardiovascular mortality occurred in 33% of placebo-treated patients ( 3029/ 10 000 person- years) and 28% of eplerenone- treated patients (2438/10 000 person- years) with Hx- HTN ( HR: 0.82; 95% CI: 0.72 to 0.94; P = 0.003). In patients without Hx- HTN, eplerenone reduced heart failure hospitalization ( HR: 73; 95% CI: 0.55 to 0.97; P = 0.028) but had no effect on mortality ( HR: 0.91; 95% CI: 0.72 to 1.15; P = 0.435) or on the composite end point ( HR: 0.91; 95% CI: 0.76 to 1.10; P = 0.331). Eplerenone should, therefore, be prescribed to all of the post - acute myocardial infarction patients with reduced left ventricular ejection fraction and heart failure regardless of Hx- HTN.

What happens after the central bank of Brazil increases the target interbank rate by 1%?

I start presenting an explicit solution to Taylorís (2001) model, in order to illustrate the link between the target interest rate and the overnight interest rate prevailing in the economy. Next, I use Vector Auto Regressions to shed some light on the evolution of key macroeconomic variables after the Central Bank of Brazil increases the target interest rate by 1%. Point estimates show a four-year accumulated output loss ranging from 0:04% (whole sample, 1980 : 1-2004 : 2; quarterly data) to 0:25% (Post-Real data only) with a Örst-year peak output response between 0:04% and 1:0%; respectively. Prices decline between 2% and 4% in a 4-year horizon. The accumulated output response is found to be between 3:5 and 6 times higher after the Real Plan than when the whole sample is considered. The 95% confidence bands obtained using bias-corrected bootstrap always include the null output response when the whole sample is used, but not when the data is restricted to the Post-Real period. Innovations to interest rates explain between 4:9% (whole sample) and 9:2% (post-Real sample) of the forecast error of GDP.

Entrepreneurship failure: is culture to blame?

Apesar de Empreendedorismo e Cultura serem tópicos com extensa literatura na área de estudos de Administração de Empresas, existe relativamente pouca pesquisa na influencia que a Cultura exerce no Empreendedorismo. O principal objetivo deste trabalho é investigar a influencia da cultura no índice de fracasso do empreendedorismo. Através de uma abordagem de correlação, utilizando 40 países da database do Hofstede (2001) de trabalhadores da IBM e dados presentes na database do Global Entrepreneurship Monitor (GEM). Os resultados desta análise sugerem que Individualismo VS. Coletivismo é a única dimensão cultural significativa quando se discute os efeitos da cultura no índice de fracasso do Empreendedorismo.

What happens after the Central Bank of Brazil increases the target interbank rate by 1%?

In this paper I use Taylor's (2001) model and Vector Auto Regressions to shed some light on the evolution of some key macroeconomic variables after the Central Bank of Brazil, through the COPOM, increases the target interest rate by 1%. From a quantitative perspective, the best estimate from the empírical analysis, obtained with a 1994 : 2 - 2004 : 2 subsample of the data, is that GDP goes through an accumulated decline, over the next four years, around 0.08%. Innovations to interest rates explain around 9.2% of the forecast erro r of GDP.

Assessing interdependence among countries' fundamentals and its implications for exchange rate misalignment estimates: An empirical exercise based on GVAR

Exchange rates are important macroeconomic prices and changes in these rates a ect economic activity, prices, interest rates, and trade ows. Methodologies have been developed in empirical exchange rate misalignment studies to evaluate whether a real e ective exchange is overvalued or undervalued. There is a vast body of literature on the determinants of long-term real exchange rates and on empirical strategies to implement the equilibrium norms obtained from theoretical models. This study seeks to contribute to this literature by showing that the global vector autoregressions model (GVAR) proposed by Pesaran and co-authors can add relevant information to the literature on measuring exchange rate misalignment. Our empirical exercise suggests that the estimate exchange rate misalignment obtained from GVAR can be quite di erent to that using the traditional cointegrated time series techniques, which treat countries as detached entities. The di erences between the two approaches are more pronounced for small and developing countries. Our results also suggest a strong interdependence among eurozone countries, as expected

Does mixed frequency vector error correction model add relevant information to exchange misalignment calculus? Evidence for United States

Real exchange rate is an important macroeconomic price in the economy and a ects economic activity, interest rates, domestic prices, trade and investiments ows among other variables. Methodologies have been developed in empirical exchange rate misalignment studies to evaluate whether a real e ective exchange is overvalued or undervalued. There is a vast body of literature on the determinants of long-term real exchange rates and on empirical strategies to implement the equilibrium norms obtained from theoretical models. This study seeks to contribute to this literature by showing that it is possible to calculate the misalignment from a mixed ointegrated vector error correction framework. An empirical exercise using United States' real exchange rate data is performed. The results suggest that the model with mixed frequency data is preferred to the models with same frequency variables

Quantization of the Proca field in the Rindler wedge and the interaction of uniformly accelerated currents with massive vector bosons from the Unruh thermal bath

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

On an acute case of Chagas disease in a region under vector control in the state of São Paulo, Brazil

Desde a década de 1970 não se notificavam casos autóctones de doença de Chagas aguda em São Paulo. em março de 2006 a Vigilância Epidemiológica registrou óbito por doença de Chagas aguda, em Itaporanga, de paciente de seis anos de idade. Exame histopatológico post mortem realizado no Hospital das Clínicas da Faculdade de Medicina de Botucatu confirmou o diagnóstico. Consultamos prontuários de hospitais e entrevistamos profissionais de saúde envolvidos além de familiares do paciente. Descrevemos medidas adotadas in loco para identificar a via de transmissão, reservatórios e vetores. Discutimos as possíveis fontes de infecção. Na região não foram identificados outros casos humanos, vetores ou reservatórios vertebrados infectados por Trypanosoma cruzi. Salientamos a importância de manter a vigilância, mesmo em áreas onde a transmissão de doença de Chagas está interrompida e naquelas ainda infestadas por triatomíneos. Deve-se admitir a hipótese diagnóstica de doença de Chagas quando observados: edema palpebral (uni ou bilateral), insuficiência cardíaca, miocardite, pericardite, anasarca, quadros similares aos de síndrome nefrótica ou glomerulonefrite sem causas outras aparentes, em pacientes com dados epidemiológicos positivos. Encontro, mesmo em raras ocasiões, de triatomíneos na região ou ainda contato com alimento contaminável com formas infectantes de T. cruzi.