Detection of failure sites by focused ion beam and nano-probing in the interconnect of three-dimensional stacked circuit structures

Focused ion beam (FIB) and nano-probing were applied for failure analysis of three-dimensional stacked circuits with copper through-silicon-vias between the stacked chips. The failure analysis was done after high temperature storage and thermal cycling tests. Passive voltage contrast in FIB allowed to pinpoint the open sites. FIB cross-sections showed the presence of opens at the bottom of the copper vias. The failure cause was suspected to be an interlayer particle, which was confirmed by optical profilometry. Nano-probing was used on another sample to pinpoint the failure location through the measurement of the local resistance within the daisy chains. The failure was traced out to be related with surface contamination.     

Elliptic curve cryptography on embedded multicore systems

The increasing use of network-connected embedded devices and online transactions creates a growing demand of network security for embedded systems. The security requirements, such as authentication, confidentiality and integrity, always make computationally intensive processes and can easily become the bottleneck of the related applications. In this paper we implement Elliptic Curve Cryptography (ECC) (Miller in Lecture Notes in Computer Science, vol. 218, pp. 417–426, 1985; Koblitz in Math. Comput. 48:203–209, 1987) on an embedded multicore system, and explore the task scheduling methods in different levels. First, we propose an instruction scheduling method that utilizes all the cores to perform one modular operation in parallel. Second, we perform multiple modular operations with multiple cores in parallel. The performance of those two implementations is compared and a scheduling method combining these two types of parallelism is proposed. We discuss the details of our proposed method by using an FPGA implementation of ECC over a prime field.     

Perceptual learning of noise vocoded words: Effects of feedback and lexicality.

Speech comprehension is resistant to acoustic distortion in the input, reflecting listeners' ability to adjust perceptual processes to match the speech input. This adjustment is reflected in improved comprehension of distorted speech with experience. For noise vocoding, a manipulation that removes spectral detail from speech, listeners' word report showed a significantly greater improvement over trials for listeners that heard clear speech presentations before rather than after hearing distorted speech (clear-then-distorted compared with distorted-then-clear feedback, in Experiment 1). This perceptual learning generalized to untrained words suggesting a sublexical locus for learning and was equivalent for word and nonword training stimuli (Experiment 2). These findings point to the crucial involvement of phonological short-term memory and top-down processes in the perceptual learning of noise-vocoded speech. Similar processes may facilitate comprehension of speech in an unfamiliar accent or following cochlear implantation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Goodness-of-fit tests in parametric regression based on the estimation of the error distribution

Consider a heteroscedastic regression model Y=m(X)+σ(X)ε, where m(X)=E(Y|X) and σ ²(X)=Var (Y|X) are unknown, and the error ε is independent of the covariate X. We propose a new type of test statistic for testing whether the regression curve m(⋅) belongs to some parametric family of regression functions. The proposed test statistic measures the distance between the empirical distribution function of the parametric and of the nonparametric residuals. The asymptotic theory of the proposed test is developed, and the proposed testing procedure is illustrated by means of a small simulation study and the analysis of a data set.     

Mixing of solids in different mixing devices

Mixing of powders is a common operation in any industry. Most powders are known to be cohesive, many agglomerate spontaneously when exposed to humid atmosphere or elevated storage temperature. Agitation of the powder (especially powders with different bulk densities) may result in migration of smaller particles downwards and of larger ones upwards. Another problem is segregation whose main cause is the difference in particle size, density shape and resilience. There are standard mixing devices, such as drum tumblers or Turbula mixers. Alternate device type used is the static mixer of Kenics type. Static mixers save energy, disable segregation and effect particle migration. In this paper, static mixers, as devices for powder mixing, are tested as well as Turbula and V-shaped drum mixer, since those devices are commonly used for powder blending in industry. Mixtures that were blended by means of those three devices were made out of the model material, quartz sand, in different component ratios (20:80 and 30:70). The results were statistically calculated and graphically presented. Cohesion indexes were measured with Powder Flow Analyser to see the effect of material flow on the mixture quality. The results obtained by those three devices, the particle size effect and cohesion indexes, bring us to the conclusion that static mixers could be used for mixing of powders, but their shape, number of mixing elements and the mixer length should be adapted for each mixture separately, experimentally and mathematically, through modelling of the system.     

A method for the identification and quantitative investigation of denatured proteins in mixtures based on computer comparison of amino-acid patterns

Summary A procedure is described in which stepwise regression is adapted to permit comparison of the amino-acid pattern from a composite sample with those of simple substances arranged in an easily accessible data bank. The computer program automatically selects from the bank those proteins whose amino-acid patterns best correspond to that of the sample, and calculates the proportion of the proteins contained in the mixture.The procedure is applicable to food analytical problems that involve the identification and determination of proteins in mixtures, and also to situations in which the properties of the proteins have been altered by denaturation or enzymatic degradation. The determination is limited to 3–4 proteins in the mixture.

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Identifizierung und quantitative Bestimmung einzelner Proteine in Mischungen von denaturierten Proteinen mit Hilfe ihrer Aminosäauremuster

Zusammenfassung Mit Hilfe einer stufenweisen Regressionsberechnung konnen Aminosäu-renmuster eines zusammengesetzten Proteins mit einfachen Proteinen verglichen werden. Mit dieser Berechnung werden aus einer Sammlung von Vergleichsproteinen automatisch solche Proteine ausgewählt, deren Aminosäurenmuster am besten zu der der Probe paßt. Gleichzeitig können dadurch die Verhältnisse der verschiedenen Proteine in der Mischung berechnet werden. Durch these Arbeitsweise konnen weiterhin bei nahrungsanalytischen Problemen Proteine in Mischungen identifiziert and quantitativ erfaßt werden, selbst worn die Proteine denaturiert oder enzymatisch abgebaut sind, jedoch ist das Verfahren auf 3–4 Proteine in der Mischung begrenzt.