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Web-based information systems development and dynamic organisational change: the need for emergent development tools
This paper considers contextual issues relating to the problem of developing web-based information
systems in and for emergent organisations. It postulates that the methods available suffer because of
sudden and unexpected changing characteristics within the organisation. The Theory of Deferred
Action is used as the basis for the development of an emergent development tool. Many tools for
managing change in a continuously changing organisation are susceptible to inadequacy. The insights
proposed are believed to assist designers in developing functional and relevant approaches within
dynamic organisational contexts
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Changes in forward light scatter parameters as a function of refractive error in young adults
Background/aims
Some aspects of visual performance worsen with increasing myopia. Whilst the underlying causes are not always clear, reduction in retinal image quality is often attributed to structural changes in the posterior myopic eye. Forward light scatter, originating principally from the cornea and lens, is known to produce veiling glare which subsequently reduces retinal image contrast. It is therefore of interest to investigate whether forward light scatter varies with refractive error.
Methods
Thirteen young-adult subjects (18–25 years), with mean spherical errors (MSE ± sd, D) RE, − 1.69 ± 2.02 (range 0.38 to − 4.75); LE, − 1.91 ± 1.94 (range 0.50 to − 4.63) underwent binocular assessment of forward light scatter using the AVOT light scatter test. Five glare annuli, with effective eccentricities ranging from 2 to 10°, were used to estimate parameters, k and n, which define the light scatter function of the eye. These were then used to calculate the area under the light scatter function (k′) and the total volume of light scatter (k″).
Results
Significant correlation was found between increasing myopia and k′ values (RE, p  0.05 for both eyes). Axial length was also not correlated with any of the light scatter parameters measured.
Conclusion
The preliminary data from this study provide evidence that some light scatter parameters may be correlated with refractive error. Further studies are needed to characterize how changes in the anterior media of the eye, and inclusion of a wider range of refractive errors, may affect forward light scatter
Discrete symmetries for electroweak natural type-I seesaw mechanism
The naturalness of electroweak scale in the models of type-I seesaw mechanism
with Yukawa couplings requires TeV scale masses for the fermion
singlets. In this case, the tiny neutrino masses have to arise from the
cancellations within the seesaw formula which are arranged by fine-tuned
correlations between the Yukawa couplings and the masses of fermion singlets.
We motivate such correlations through the framework of discrete symmetries. In
the case of three Majorana fermion singlets, it is shown that the exact
cancellation arranged by the discrete symmetries in seesaw formula necessarily
leads to two mass degenerate fermion singlets. The remaining fermion singlet
decouples completely from the standard model. We provide two candidate models
based on the groups and and discuss the generic
perturbations to this approach which can lead to the viable neutrino masses.Comment: 26 pages, 4 figures; references added, matches published versio
Active Authentication using an Autoencoder regularized CNN-based One-Class Classifier
Active authentication refers to the process in which users are unobtrusively
monitored and authenticated continuously throughout their interactions with
mobile devices. Generally, an active authentication problem is modelled as a
one class classification problem due to the unavailability of data from the
impostor users. Normally, the enrolled user is considered as the target class
(genuine) and the unauthorized users are considered as unknown classes
(impostor). We propose a convolutional neural network (CNN) based approach for
one class classification in which a zero centered Gaussian noise and an
autoencoder are used to model the pseudo-negative class and to regularize the
network to learn meaningful feature representations for one class data,
respectively. The overall network is trained using a combination of the
cross-entropy and the reconstruction error losses. A key feature of the
proposed approach is that any pre-trained CNN can be used as the base network
for one class classification. Effectiveness of the proposed framework is
demonstrated using three publically available face-based active authentication
datasets and it is shown that the proposed method achieves superior performance
compared to the traditional one class classification methods. The source code
is available at: github.com/otkupjnoz/oc-acnn.Comment: Accepted and to appear at AFGR 201
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