Failure Analysis of Fan Motor Shafts of a Tunnel Dryer

This article details the analysis of two conducting shafts operating on blowers of a tunnel dryer. A deductive analysis was applied looking toward a successful recognition of root cause(s), where based on knowledge of background, and failure characteristics, multiple hypothesis are exposed that are further confirmed or rejected according to different tests, material analysis or maintenance history. In both shafts, failure arises from inadequate repairing. In order to confirm this, the failure analysis methodology included the following steps: technical review, visual inspection, fractography, penetrating inks, metallography, optic microscopy and stress analysis. Evidence obtained through these techniques indicates a fatigue failure induced by inadequate repairing procedures; therefore, main recommendation is to take the necessary precautions in order to guarantee minimal alterations on shaft geometry or material microstructure.     

On the joint effects of stimulus quality, regularity, and lexicality when reading aloud: New challenges.

A number of computational models have been developed over the last 2 decades that are remarkably successful at explaining the process of translating print into sound. Nevertheless, 2 of the most successful computational accounts on the table fail to simulate the results from factorial experiments reported in this article in which university students read aloud letter strings that varied in terms of spelling–sound regularity and lexicality (regular words vs. exception words vs. nonwords) and stimulus quality (bright vs. dim). Skilled readers yielded additive effects of regularity and stimulus quality and additive effects of lexicality and stimulus quality on both RT and errors when nonwords were mixed with words. When only words appeared in the list, there was an interaction in which exception words were less affected by low stimulus quality than regular words were; no existing account anticipates or explains these results. We advance a hypothesis that assumes a novel module that accommodates these data and provide an existence proof in the form of a simulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual word recognition: Evidence for global and local control over semantic feedback.

Two lexical decision experiments examined the joint effects of stimulus quality, semantic context, and cue-target associative strength when all factors were intermixed in a block of trials. Both experiments found a three-way interaction. Semantic context and stimulus quality interacted when associative strength between cue-target pairs was strong, and the interaction was eliminated when the strength was weak. These results support a role for a local mechanism that relies on trial specific information, in addition to a mechanism that makes use of global information available across a block of trials. The absence of an interaction between the joint effects of semantic context and stimulus quality is attributed to blocking the feedback from the semantic system to the orthographic system, functionally separating the orthographic and semantic modules. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reading aloud: Evidence for contextual control over lexical activation.

Can readers exert control (albeit unconsciously) over activation at particular loci in the reading system? The authors addressed this issue in 4 experiments in which participants read target words aloud and the factors of prime–target relation (semantic, repetition), context (related, unrelated), stimulus quality (bright, dim), and relatedness proportion (RP; high, low) were manipulated. In the high RP condition (RP = .5), an interaction between semantic context and stimulus quality was observed in which low stimulus quality slowed unrelated targets more than related ones, replicating previous work. In contrast, the low RP condition (RP = .25) yielded additive effects of semantic context and stimulus quality. However, when low RP was examined within the context of repetition priming, context and stimulus quality once again interacted. These results are discussed in the context of a widely endorsed framework with the addition of the central assumption that there is control over feedback between various levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When benefits outweigh costs: Reconsidering “automatic” phonological recoding when reading aloud.

Skilled readers are slower to read aloud exception words (e.g., PINT) than regular words (e.g., MINT). In the case of exception words, sublexical knowledge competes with the correct pronunciation driven by lexical knowledge, whereas no such competition occurs for regular words. The dominant view is that the cost of this “regularity” effect is evidence that sublexical spelling-sound conversion is impossible to prevent (i.e., is “automatic”). This view has become so reified that the field rarely questions it. However, the results of simulations from the most successful computational models on the table suggest that the claim of “automatic” sublexical phonological recoding is premature given that there is also a benefit conferred by sublexical processing. Taken together with evidence from skilled readers that sublexical phonological recoding can be stopped, we suggest that the field is too narrowly focused when it asserts that sublexical phonological recoding is “automatic” and that a broader, more nuanced and contextually driven approach provides a more useful framework. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Constraints on computational models of basic processes in reading.

There are numerous reports in the visual word recognition literature that the joint effects of various factors are additive on reaction time. A central claim by D. C. Plaut and J. R. Booth (2000, 2006) is that their parallel distributed processing model simulates additive effects of stimulus quality and word frequency in the context of lexical decision. If correct, this success would have important implications for computational accounts of reading processes. However, the results of further simulations with this model undermine this claim given that the joint effects of stimulus quality and word frequency yield a nonmonotonic function (underadditivity, additivity, and overadditivity) depending on the size of the stimulus quality effect, whereas skilled readers yield additivity more broadly. The implications of these results both locally and more globally are discussed, and a number of other issues are noted. Additivity of factor effects constitutes a benchmark that computational accounts should strive to meet. (PsycINFO Database Record (c) 2010 APA, all rights reserved)