A digital signal processing system developed for the optimal use of high density magnetic storage media

High density data recording has traditionally been an essential factor in the development of communication and transmission systems. However, recently more sophisticated applications, including video recording, have necessitated refinements of this technology. This study concentrates on the signal processing techniques used to inhance the packing density of stored data. A comparison of the spectral mapping characteristics of different codes illustrates that the need for equalization can be eliminated and that significant bandwidth reduction can be achieved. Secondly, consideration is given to the deleterious effects of flutter, its associated effects on high density data recording, and the constraints imposed on the development of a time base corrector. An analysis is made of the bandlimiting effect which results when the incoming data is convolved with the head impulse response. The bandwidth of the channel, the size of the head gap, and the velocity of the media are seen from this analysis to be intrinsically related. These signal processing techniques are implemented, the channel capacity computed, and a significant channel efficiency achieved

A Case Study of the Development of a Career Academy: Good Intentions Not Enough?

The purpose of this study was to explore how a career academy featuring an information technology (IT) theme approached the adoption of the model and the particular curricular focus. We used a case study design to explore the experiences of school personnel and community partners associated with the implementation of the career academy. We found that growing enrollment in the local district was a major driver to pursue small school designs as an alternative to the traditional high school comprehensive model. The small school size associated with small learning communities was valued by stakeholders and used to adopt and implement a career academy around a technology curricular theme. Another factor in the adoption decision was the availability of existing building infrastructure in the community. While the premises of the career academy model appeared to be a good fit in the district and community, we also found that good intentions are not enough to guarantee consistent fidelity throughout the career academy implementation. When new crises arise, input from all stakeholders may be shortchanged and decisions can turn into a top-down approach

Lagrangian Flow Network approach to an open flow model

Concepts and tools from network theory, the so-called Lagrangian Flow Network framework, have been successfully used to obtain a coarse-grained description of transport by closed fluid flows. Here we explore the application of this methodology to open chaotic flows, and check it with numerical results for a model open flow, namely a jet with a localized wave perturbation. We find that network nodes with high values of out-degree and of finite-time entropy in the forward-in-time direction identify the location of the chaotic saddle and its stable manifold, whereas nodes with high in-degree and backwards finite-time entropy highlight the location of the saddle and its unstable manifold. The cyclic clustering coefficient, associated to the presence of periodic orbits, takes non-vanishing values at the location of the saddle itself.Comment: 7 pages, 3 figures. To appear in European Physical Journal Special Topics, Topical Issue on "Recent Advances in Nonlinear Dynamics and Complex Structures: Fundamentals and Applications

Promoting Active and Sustained School-Business Partnerships: An Exploratory Case Study of an IT Academy

In support of the national push for promoting career readiness, school-business partnerships have been noted as an important support strategy. However, there is limited research in the context of career academies. Thus, we sought to explore the nature of a partnership between an information technology (IT) career academy and local business partners. We found that the development of social capital is required to keep the network of partners bonded toward a common goal, bridged through a Business Advisory Council to facilitate planning and related supports, and linked by a local web of connecting relationships. Study findings add to the limited literature on the interface of school-business partnerships, career academies, and the promotion of career readiness in particular occupational contexts such as IT