Effect of fault tolerance and communication delay on response time in a multiprocessor system with a bus topology

The effect of interprocessor communication and fault tolerance on the response time of N processors (nodes) interconnected through a bus type communication medium is discussed. Deterministic as well as probabilistic approaches are considered. Four correction methods to handle the unprocessed data by the faulty processor(s) are studied and compared. It is found that the effect of interprocessor communication and fault tolerance on the response time for communication-extensive programs (I/O bound) is more than that for computation-extensive programs (CPU bound). It is also found that the effect of fault tolerance on the response time is significant, and cannot be ignored when evaluating the performance of multiprocessor systems. We have shown that the work presented in this paper for a bus topology can be generalized and readily adopted by other multiprocessor network topologies.     

A survey on the use of pattern recognition methods for abstraction, indexing and retrieval of images and video

The need for content-based access to image and video information from media archives has captured the attention of researchers in recent years. Research efforts have led to the development of methods that provide access to image and video data. These methods have their roots in pattern recognition. The methods are used to determine the similarity in the visual information content extracted from low level features. These features are then clustered for generation of database indices. This paper presents a comprehensive survey on the use of these pattern recognition methods which enable image and video retrieval by content.     

Aging, source memory, and misrecollections.

The authors propose an illusory recollection account of why cognitive aging is associated with episodic memory deficits. After listening to statements presented by either a female or a male speaker, older adults were prone to misrecollecting past events. The authors' illusory recollection account is instantiated in a new illusory recollection signal detection model that provides a better fit of older adults' data than does the standard signal detection model. They observed that age-related differences in source memory (as measured by source d′ scores) virtually disappear after accounting for the occurrence of illusory recollections. These data suggest that age-related source memory impairments are not due to older adults' remembering less diagnostic source information and having to guess more. Instead, older adults appear to misremember past events more often than younger adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Technology in Engineering Education: What Do the Faculty Know and Want?

There currently exists a great interest in integrating technology into the engineering curriculum. The Southeastern University and College Coalition for Engineering Education (SUCCEED) has identified this topic to be one of four “focus areas” for the coalition, and is committed to supporting the effective use of technology in enhancing the learning and teaching environment. We report here the results of a survey of engineering faculty at the coalition universities to identify the training needs and present levels of experience with various technologies. The most surprising finding is that, despite the wide differences in the Coalition's colleges of engineering, the survey results are similar for all campuses. This implies that the results may be widely applicable to other universities. Generally, we found that the faculty's interest in receiving training in a specific technology is highly correlated with a low skill level for that topic, as expected. Of the ten potential workshop topics, those in highest demand include:

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Episode detection in videos captured using a head-mounted camera

With the advent of wearable computing, personal imaging, photojournalism and personal video diaries, the need for automated archiving of the videos captured by them has become quite pressing. The principal device used to capture the human-environment interaction with these devices is a wearable camera (usually a head-mounted camera). The videos obtained from such a camera are raw and unedited versions of the visual interaction of the wearer (the user of the camera) with the surroundings. The focus of our research is to develop post-processing techniques that can automatically abstract videos based on episode detection. An episode is defined as a part of the video that was captured when the user was interested in an external event and paid attention to record it. Our research is based on the assumption that head movements have distinguishable patterns during an episode occurrence and these patterns can be exploited to differentiate between an episode and a non-episode. Here we present a novel algorithm exploiting the head and body behaviour for detecting the episodes. The algorithms performance is measured by comparing the ground truth (user-declared episodes) with the detected episodes. The experiments show the high degree of success we achieved with our proposed method on several hours of head-mounted video captured in varying locations.     

Optimal Design in the Presence of Modeling Uncertainties

The integration of modeling and simulation tools with robust and efficient methods of optimal design offers a rational approach to explore new concepts and designs. However, a widespread adaptation of these tools in the industry design environment will require that they incorporate a systematic analysis of uncertainty in all aspects of the design process. A lack of confidence in designs generated in a simulation-based approach is the result of uncertainties in the predictive capabilities of physics-based models used in the simulations, and poor representation of uncertainties and their propagation in a coupled systems engineering design problem. A data- and knowledge-lean environment, typical of a design process involving novel concepts, further exacerbates the situation; design engineers often make gross assumptions about distributional information of random variables and parameters, thereby adding to the uncertainty associated with the design results. The paper focuses on numerical and analytical tools by which to model uncertainty and risk in a simulation-based design environment, including cases where the uncertainty does not conform to standard probabilistic distributions. A specific focus of the modeling effort is an approach to establish confidence intervals for response predictions available from analytical and numerical models, as well as surrogate approximations used in the design process. Innovative adaptations of formal optimization methods in a nondeterministic design setting are discussed, including design problem formulations that examine the nondeterministic design problem in a multicriteria optimization framework. Simple design problems are used to illustrate the concepts and to underscore the deficiencies in a purely deterministic approach to the design problem.     

Neural network analysis of MINERVA scene image benchmark

Scene analysis is an important area of research with the aim of identifying objects and their relationships in natural scenes. MINERVA benchmark has been recently introduced in this area for testing different image processing and classification schemes. In this paper we present results on the classification of eight natural objects in the complete set of 448 natural images using neural networks. An exhaustive set of experiments with this benchmark has been conducted using four different segmentation methods and five texture-based feature extraction methods. The results in this paper show the performance of a neural network classifier on a tenfold cross-validation task. On the basis of the results produced, we are able to rank how well different image segmentation algorithms are suited to the task of region of interest identification in these images, and we also see how well texture extraction algorithms rank on the basis of classification results.     

Optimizing size and distribution of voids in phenolic resins through the choice of catalyst types

Phenolics are widely used for over a century in different industries due to their chemical resistance and thermomechanical properties. However, the presence of voids in phenolic resins has negative effects on the mechanical properties and a conventional approach is to avoid these by utilizing very long cure cycles. Our alternative approach investigates the tailoring of void size and distribution to achieve a better balance between processing time and mechanical properties. Therefore, we produced phenolic resin with a void-free microstructure by a long cure cycle as a reference. To alter the void size and distributions, we utilized different catalysts and a short cure cycle to obtain phenolic resins and test their flexural properties with respect to the reference. We investigated the fracture surfaces of all materials by SEM, FTIR and compared results to finite element modeling that confirmed the effects of different void size and distributions on the mechanical properties. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48249.     

Development and validation of a simple analytical method for the determination of 2,4,6-trichloroanisole in wine by GC–MS

A novel method for the residue analysis of wine spoilage compound 2,4,6-trichloroanisole is reported. Wine (60 ml) was extracted with 2 ml toluene in presence of 24 g MgSO₄ and 6 g NaCl. Cleanup of the toluene phase by dispersive solid phase extraction with mixture of 100 mg CaCl₂, 25 mg primary secondary amine and 50 mg MgSO₄ was effective in minimising co-extractives and matrix effects. Time-of-flight and tandem mass spectrometric parameters were optimised to achieve linearity over 0.25–500 ng ml⁻¹ and method detection limit 0.0083 ng ml⁻¹ which is well below the odour threshold of 0.04 ng ml⁻¹. Recoveries at 0.04, 0.2 and 0.8 ng ml⁻¹ were within 80–110% (±8%). The method was reproducible when tested for Argentinean wines with intra-laboratory Horwitz ratios being <0.20 in white and red wines at both the laboratories of India and Argentina. The method could be successfully applied for incurred wine samples.