A Practical Vulnerability Assessment Program

Firewalls, malicious-code-screening servers, and intrusion-detection systems aren't sufficiently comprehensive to ensure appropriate and ongoing information confidentiality, integrity, and availability. A practical vulnerability assessment program lets organizations identify potential security exposures and correct any deficiencies.     

The Cognitive Benefit of Dynamic Representations on Procedural Skill Acquisition: A Computational Modeling Approach

Cognitive computational modeling is a viable methodology for further investigation of the hitherto inconclusive findings on the cognitive benefits of dynamic versus static visualization components of instructions. This is more so as contemporary cognitive architectures such as the Adaptive Control of Thought–Rational (ACT–R) 6.0 are increasingly applied to traditional cognitive psychology research problems. The application of this methodology is, however, restricted by the limited capability of existing architectures for implementing detailed atomic motor actions such as those involved in complex skill acquisition and performance. This article presents a 2-component computational modeling methodology for investigating the cognitive processes involved in the acquisition and performance of skilled motor tasks. The approach specifies a novel combination of a sequence-of-point technique with a movement control mechanism to implement variously acquired cognitive mental task representations and their intertwined role in postlearning performance as evident in the atomic control of motor actions. This paradigm is validated for 2 experiments using incrementally developed cognitive models developed in ACT–R 6.0. The model's quantitative outputs correlate significantly with equivalent empirical human data. This has implications for multimedia instructional design, especially where rapid, transferrable skill acquisition is desired on initial exposure.     

Examining student satisfaction with wholly online learning

Learner satisfaction has been shown to be positively correlated with quality of learning outcomes. An understanding of the factors that influence student satisfaction with online learning in a particular context can be used as an input to the appropriate design of learning environments, and for the provision of targeted support to students, with an aim to positively influence the student online learning experience. Following the mandatory inclusion of at least one wholly online unit of study in all undergraduate programs at Deakin University, a large 'experiences of learning online' (ELO) survey was undertaken to gauge students' perceptions of studying in the wholly online mode. A multivariate linear regression of all the questionnaire items was performed against an overall satisfaction item. Five items were found to significantly contribute to a model that explained approximately 70% of reported student satisfaction. Factors that were found to positively influence student satisfaction with studying a wholly online unit primarily related to how confident they felt about their ability to communicate and learn online, having a clear understanding of what was required to succeed in the unit and how well they thought they were performing in the unit. Other results are also reported.     

Scattering Parameters Representing Imperfections in Precision Coaxial Air Lines

Scattering parameter expressions are developed for the principal mode of a coaxial air line. The model allows for skin-effect loss and dimensional variations in the inner and outer conductors. Small deviations from conductor circular cross sections are conformally mapped by the Bergman kernel technique. Numerical results are illustrated for a 7 mm air line. An error analysis reveals that the accuracy of the scattering parameters is limited primarily by the conductor radii measurement precision.     

Classification of osteoarthritic and normal knee function using three-dimensional motion analysis and the Dempster-Shafer theory of evidence

In this paper, a novel object classification method is introduced and developed within a biomechanical study of human knee function in which subjects are classified to one of two groups: subjects with osteoarthritic (OA) and normal (NL) knee function. Knee-function characteristics are collected using a three-dimensional motion-analysis technique. The classification method transforms these characteristics into sets of three belief values: a level of belief that a subject has OA knee function, a level of belief that a subject has NL knee function, and an associated level of uncertainty. The evidence from each characteristic is then combined into a final set of belief values, which is used to classify subjects. The final belief values are subsequently represented on a simplex plot, which enables the classification of a subject to be represented visually. The control parameters, which are intrinsic to the classification method, can be chosen by an expert or by an optimization approach. Using a leave-one-out cross-validation approach, the classification accuracy of the proposed method is shown to compare favorably with that of a well-established classifier-linear discriminant analysis. Overall, this study introduces a visual tool that can be used to support orthopaedic surgeons when making clinical decisions.     

Surface polarity and symmetry in semiconducting compounds

The polarity of the crystallographic surfaces of semiconducting compounds with the sphalerite and wurtzite structures results in gross differences in macroscopic chemical, mechanical and crystal growth behaviour which are reviewed. The asymmetry of the orthogonal 1 1 0 directions in {100} surfaces of sphalerite structure materials is manifested in phenomena arising from {1 1 1}A- B differences. To treat these phenomena the surface polarity index and the singular surface polyhedra for sphalerite- and wurtzite-structure semconducting compounds are introduced.     

The relationship between HMW glutenin subunit composition and the bread-making quality of British-grown wheat varieties

Based on previous work, which related individual HMW glutenin subunits to bread-making quality by genetical analysis, quality scores were assigned to each of the commonly occurring subunits. The grain proteins of 84 home-grown wheat varieties were fractionated by SDS—PAGE to determine their HMW glutenin subunit composition. The quality scores of each of the subunits were summed to create a Glu-1 quality score for each variety. The results indicated that 47-60% of the variation in the independently established bread-making qualities of this set of varieties could be accounted for by variation in HMW subunits of glutenin. The presence or absence in the varieties of a translocated chromosome, which consisted of the long arm of 1B and the short arm of 1R from rye, was also established because of its known association with poor bread-making quality. A correction factor was applied to the Glu-1 quality score of those varieties that contained the 1 BLURS chromosome. The variations in the rye-adjusted Glu-1 quality scores were compared with those of the bread-making qualities of the varieties, and the proportion of variation in quality accounted for was raised to 55-67%. The Glu-1 quality score and the biscuit-making qualities of the same set of varieties were negatively related. The results are discussed in relation to future strategies recommended to wheat breeders for developing new varieties with improved bread-making quality.     

Specific recognition of HLA-E, but not classical, HLA class I molecules by soluble CD94/NKG2A and NK cells

The CD94/NKG2 receptors expressed by subpopulations of NK cells and T cells have been implicated as receptors for a broad range of both classical and nonclassical HLA class I molecules. To examine the ligand specificity of CD94/NKG2 proteins, a soluble heterodimeric form of the receptor was produced and used in direct binding studies with cells expressing defined HLA class I/peptide complexes. We confirm that CD94/NKG2A specifically interacts with HLA-E and demonstrate that this interaction is dependent on the association of HLA-E with peptide. Moreover, no interaction between CD94/NKG2A and classical HLA class I molecules was observed, as assayed by direct binding of the soluble receptor or by functional assays using CD94/NKG2A+ NK cells. The role of the peptide associated with HLA-E in the interaction between HLA-E and CD94/NKG2A was also assessed. All class I leader sequence peptides tested bound to HLA-E and were recognized by CD94/NKG2A. However, amino acid variations in class I leader sequences affected the stability of HLA-E. Additionally, not all HLA-E/peptide complexes examined were recognized by CD94/NKG2A. Thus CD94/NKG2A recognition of HLA-E is controlled by peptide at two levels; first, peptide must stabilize HLA-E and promote cell surface expression, and second, the HLA-E/peptide complex must form the ligand for CD94/NKG2A.