pth Moment exponential stability of impulsive stochastic functional differential equations and application to control problems of NNs

This paper investigates the pth moment exponential stability of impulsive stochastic functional differential equations. Some sufficient conditions are obtained to ensure the pth moment exponential stability of the equilibrium solution by the Razumikhin method and Lyapunov functions. Based on these results, we further discuss the pth moment exponential stability of generalized impulsive delay stochastic differential equations and stochastic Hopfield neural networks with multiple time-varying delays from the impulsive control point of view. The results derived in this paper improve and generalize some recent works reported in the literature. Moreover, we see that impulses do contribute to the stability of stochastic functional differential equations. Finally, two numerical examples are provided to demonstrate the efficiency of the results obtained.     

‘The otherness that implicates the self’: towards an understanding of gendering from a theory of proximity

In this article, I consider ways in which the concept of “proximity” can be put to work to understand how gendering occurs in the conduct of gender research – the theme of this special issue. If we accept that researchers are always already inside and implicated in the issues into which they inquire, and that they simultaneously establish an outside position which enables them to notice patterns, make inferences, and develop understandings, then we can say that researchers are always in proximity to something, and that this proximity, inherited or otherwise, places objects, capacities, and understandings within their reach, while also permitting them to extend their reach. In this article, I consider what happens in gender research contexts when researchers register certain proximities, fail to see others, or deny those that make them uncomfortable. Framed by my ongoing research into place cultures in boys’ schools, I argue that thinking gender research practices with the concept of “proximity” pushes researchers to think beyond essentializing accounts of how they gender and are gendered in doing gender research.     

Controllability of Volterra-Fredholm type systems in Banach spaces

We show the results in Chalishajar [Controllability of mixed Volterra-Fredholm-type integro-differential systems in Banach space, J. Franklin Inst. 344(1) (2007) 12-21] and Chang and Chalishajar [Controllability of mixed Volterra-Fredholm type integro-differential systems in Banach space, J. Franklin Inst., doi:10.1016/j.jfranklin.2008.02.002] are only valid for ordinary differential control systems. As a result the examples provided cannot be recovered as applications of the abstract results.     

A Heuristic Framework of Spatial Ability: a Review and Synthesis of Spatial Factor Literature to Support its Translation into STEM Education

An abundance of empirical evidence exists identifying a significant correlation between spatial ability and educational performance particularly in science, technology, engineering and mathematics (STEM). Despite this evidence, a causal explanation has yet to be identified. Pertinent research illustrates that spatial ability can be developed and that doing so has positive educational effects. However, contention exists within the relevant literature concerning the explicit definition for spatial ability. There is therefore a need to define spatial ability relative to empirical evidence which in this circumstance relates to its factor structure. Substantial empirical evidence supports the existence of unique spatial factors not represented in modern frameworks. Further understanding such factors can support the development of educational interventions to increase their efficacy and related effects in STEM education. It may also lead to the identification of why spatial ability has such a significant impact on STEM educational achievement as examining more factors in practice can help in deducing which are most important. In light of this, a synthesis of the spatial factors offered within existing frameworks with those suggested within contemporary studies is presented to guide further investigation and the translation of spatial ability research to further enhance learning in STEM education.     

Spatial cognition in engineering education: developing a spatial ability framework to support the translation of theory into practice

ABSTRACT

A substantial degree of empirical evidence has illustrated the correlation between spatial skills and performance in engineering education. This evidence has been foundational in the construction of educational interventions which have resulted in both increased levels of spatial ability and increased educational performance and retention. However, the cognitive faculty of spatial cognition is widely recognised as multifactorial and a number of factors exist within this domain which have not been examined as potential influences on educational success. A number of factors have been identified within the pertinent literature which do not appear in any formal framework of spatial cognition. This paper presents a review and synthesis of this work with the amalgam presented as a model to support the further integration of spatial ability into engineering educational practices.