Effect of curing moisture on the indentation force deflection of flexible polyurethane foam

The moisture effect on the indentation force deflection (IFD) of flexible polyurethane foam was examined through the curing of the foam with different moisture contents. The employed foam was cured at 30, 40, 50, 60, 70, and 80% relative humidity, and the corresponding curing temperature was constant at 23°C. The experiments showed that the measured IFD and support factor of the flexible polyurethane foam decreased, and the hysteresis increased with the curing moisture. A statistical conversion formula was generated experimentally to correct the measured IFD of the flexible polyurethane foam to eliminate the deviation caused by the moisture effect. The measured IFD was inversely exponentially proportional to the curing moisture. The accuracy of the correction formula was verified by the conditioning of the foam again with different moisture contents. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1679–1682, 2007     

Cysteine‐Rich Antifungal Proteins from Filamentous Fungi are Promising Bioactive Natural Compounds in Anti‐Candida Therapy

The emerging number of life‐threatening invasive fungal infections caused by drug‐resistant Candida strains urges the need for the development and application of fundamentally new and safe antifungal strategies in the clinical treatment. Recent studies demonstrated that the extracellular cysteine‐rich and cationic antifungal proteins (crAFPs) originating from filamentous fungi, and de novo designed synthetic peptide derivatives of these crAFPs provide a feasible basis for this approach. This mini‐review focuses on the global challenges of the anti‐Canidia therapy and on the crAFPs as potential drug candidates to overcome existing problems. The advantages and limitations in the use of crAFPs and peptide derivatives compared to those of conventional antifungal drugs will also be critically discussed.     

Efficient mixing of viscoelastic fluids in a microchannel at low Reynolds number

In this paper, we examined mixing of various two-fluid flows in a silicon/glass microchannel based on the competition of dominant forces in a flow field, namely viscous/elastic, viscous/viscous and viscous/inertial. Experiments were performed over a range of Deborah and Reynolds numbers (0.36 < De < 278, 0.005 < Re < 24.2). Fluorescent dye and microshperes were used to characterize the flow kinematics. Employing abrupt convergent/divergent channel geometry, we achieved efficient mixing of two-dissimilar viscoelastic fluids at very low Reynolds number. Enhanced mixing was achieved through elastically induced flow instability at negligible diffusion and inertial effects (i.e. enormous Peclet and Elasticity numbers). This viscoelastic mixing was achieved over a short effective mixing length and relatively fast flow velocities.     

An Effective Technique for Subpixel Image Registration Under Noisy Conditions

This paper proposes an effective higher order statistics method to address subpixel image registration. Conventional power spectrum-based techniques employ second-order statistics to estimate subpixel translation between two images. They are, however, susceptible to noise, thereby leading to significant performance deterioration in low signal-to-noise ratio environments or in the presence of cross-correlated channel noise. In view of this, we propose a bispectrum-based approach to alleviate this difficulty. The new method utilizes the characteristics of bispectrum to suppress Gaussian noise. It develops a phase relationship between the image pair and estimates the subpixel translation by solving a set of nonlinear equations. Experimental results show that the proposed technique provides performance improvement over conventional power-spectrum-based methods under different noise levels and conditions.     

A Simultaneous Search Problem

We introduce a new search problem motivated by computational metrology. The problem is as follows: we would like to locate two unknown numbers x,y ∈ [0,1] with as little uncertainty as possible, using some given number k of probes. Each probe is specified by a real number r∈ [0,1] . After a probe at r , we are told whether x≤ r or x \geq r , and whether y≤ r or y\geq r . We derive the optimal strategy and prove that the asymptotic behavior of the total uncertainty after k probes is 13/7 2 ^-(k+1)/2 for odd k and 13/10 2 ^-k/2 for even k . Received November 11, 1996; revised October 2, 1997, and July 13, 1998.     

The ontogeny of fear-potentiated startle: Effects of earlier-acquired fear memories.

Research has shown that learned fear emerges in a response-specific sequence. For example, freezing is observed at a younger age than is potentiated startle (P. Hunt & B. A. Campbell, 1997). The present study shows that the age at which a specific learned fear response emerges is influenced by the animal's early experiences. Specifically, fear potentiation of startle emerges earlier in development if the rat is given prior fear conditioning to a different stimulus. Some constraints of this "facilitation" effect are determined in follow-up experiments. This facilitation effect may provide a novel way of testing the development of the neural circuits underlying learned fear. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An MDD-based generalized arc consistency algorithm for positive and negative table constraints and some global constraints

A table constraint is explicitly represented as its set of solutions or non-solutions. This ad hoc (or extensional) representation may require space exponential to the arity of the constraint, making enforcing GAC expensive. In this paper, we address the space and time inefficiencies simultaneously by presenting the mddc constraint. mddc is a global constraint that represents its (non-)solutions with a multi-valued decision diagram (MDD). The MDD-based representation has the advantage that it can be exponentially smaller than a table. The associated GAC algorithm (called mddc) has time complexity linear to the size of the MDD, and achieves full incrementality in constant time. In addition, we show how to convert a positive or negative table constraint into an mddc constraint in time linear to the size of the table. Our experiments on structured problems, car sequencing and still-life, show that mddc is also a fast GAC algorithm for some global constraints such as sequence and regular. We also show that mddc is faster than the state-of-the-art generic GAC algorithms in Gent et al. (2007), Lecoutre and Szymanek (2006), Lhomme and Régin (2005) for table constraint.     

Knowledge construction and misconstruction: A case study approach in asynchronous discussion using Knowledge Construction – Message Map (KCMM) and Knowledge Construction – Message Graph (KCMG)

This paper introduces a methodology for analyzing the knowledge construction and misconstruction processes occurring in online asynchronous discussion for Secondary 2 (Grade 8) students. The use of purposive sampling targeting specific students in a single course forum could potentially advance understanding of these processes using Knowledge Construction – Message Map (KCMM) and Knowledge Construction – Message Graph (KCMG). This paper traced the communication patterns and knowledge construction as well as misconstruction processes of students working in groups to formulate scientific ideas. This methodology reveals the dynamics of asynchronous discussion through mapping and quantifying the electronic learning process. This will equip educational practitioners and researchers with a useful tool for describing online interaction through adoption of a measurement methodology more systematic and effective than anecdotally. The research findings suggest that self-directed learning through asynchronous discussion has to be monitored by facilitators as learners possessed misconceptions that could potentially mislead other participants.     

Subband Synthesis for Color Filter Array Demosaicking

This paper presents a new algorithm for demosaicking images captured through a color filter array (CFA). The objective of the CFA demosaicking is to render a full color image from the mosaicked image. This is commonly achieved by estimating the missing color information from the surrounding observed pixels. In this paper, we integrate the observation that color images have a strong intrachannel spatial correlation in low-frequency components and a dominant interchannel correlation in the high- frequency components. A new framework is proposed to utilize this information where the missing pixels in each color channel are estimated from the wavelet subbands. A modified median-filtering operation is then applied in the subband domain. The algorithm is adaptive and produces superior full-resolution images when compared with other methods.     

Integrating functional,social, and psychological determinants to explain online social networking usage

People involved in business are increasingly aware of the online social phenomenon and its potential as a marketing tool. Building upon the marketing, social psychology, and information system literature, this study empirically examines a set of functional determinants derived from the technology acceptance model and socio-psychological determinants drawn from the theory of reasoned action and social cognitive theory that may be responsible for the motivations of participants in online social networks. We propose a model by integrating functional, social, and psychological factors in predicting attitude and online social network usage. The survey outcomes from a cross-sectional study among 387 Facebook users in Malaysia support the hypothesised model. This study contributes by extending the cognitive learning theories in predicting online social networking usage. Particularly, this research presents a different perspective on online social networking by exploring the mediating effect of attitude and the moderating role of individual characteristics. This study demonstrates that desirable changes in the perception of functional benefits, self-efficacy, and need for cognition as well as perceptions of social pressure from significant others might lead to corresponding changes in attitude towards online social networking. Results of the study support the model efficacy and predictive ability of the proposed integrative model which may serve as a theoretical foundation for future researchers interested in examining other virtual community engagements such as blogging, online advertising, and online public relations activities.