South African Higher Education has gone through various changes and challenges, one of these being the merger process. Various Universities and Technikons were forced to merge in an effort to aid the transformation and restructuring of the Higher Education landscape in the post-apartheid era. From an ICT point of view, the merged Institutions ended up with massive and distributed computing facilities. These facilities must be managed and secured and it can be appreciated that the complexity and magnitude of this task is compounded by the large and varied user population (i.e. students) using the facilities. With the exploding use of mobile consumer devices (such as cell phones, personal digital assistants, MP3 players, portable storage devices such as flash drives, etc), Higher Education Institutions are faced with the even more complex task of managing and securing the computing infrastructure, while large numbers of students can enter computer labs and use these devices at random. In some circles, portable devices are touted to be the next panacea in higher education. This, together with the popularity these devices enjoy under the student body, makes it a fait accompli that mobile consumer devices are “here to stay”. Therefore, banning these devices from campus computer labs, is not viable. Universities have to find ways to address security issues through the implementation of appropriate protective measures. This research focuses on finding a solution to mitigating the risks imposed on Higher Education Institutions in South Africa caused by the use of portable storage devices. The research proposes a framework which serves as an outline for the countermeasures that Universities must implement to mitigate the risks inherent to the use of portable storage devices. The scope of the research is limited to flash drives, smart phones and MP3 players.

Call number: LD2668 .T4 1956 K31 / Master of Science

Multi-track run-length-limited (d,k) modulation codes were recently introduced as a method to increase storage densities in magnetic and optical recording systems. These codes are a generalization of the usual run-length-limited (d,k) codes and provide for increased storage density by relaxing the k-constraint and encoding multiple tracks in parallel. This dissertation focuses on methods of constructing such codes. Two methods are presented. The first uses state-splitting to construct multi-track (d,k) trellis codes. An example is presented in which a (1,3) trellis code is constructed having a code rate of R = 2/3. The second method results in the construction of multi-track (d,k) block codes which are implemented via an enumeration scheme based on the trellis description of the (d,k) constraints. This implementation results in memory requirements which increase only linearly with block length as opposed to the exponential increases arising from look-up table implementations. Additionally, a new class of multi-track codes referred to as redundant multi-track (d,k) codes, is introduced. These redundant codes, unlike the original multi-track (d,k) codes which are completely intolerant of faulty tracks, allow for r faulty tracks while maintaining synchronization.

Direct measurement of optical phase is used in a high-density optical disk reader. The increased density is achieved by introducing multiple pit depths to replace the single pit depths of a traditional compact disk. Having four independent pit depths can double the storage capacity of a disk. The multi-level pits are read by direct measurement of the phase difference between two laser spots focused onto the disk surface. Extraction of phase information utilizes the equations of phase shifting interferometry with four shifted fringe patterns created simultaneously by a compact optical head. The system speed is therefore limited by the readout electronics instead of by slow mechanical phase shifters. The resulting system can identify four independent levels as well as the direction of transition from one level to another. The system also has low sensitivity to vibrations and to changes in the fringe contrast and beam intensity.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Vita. / Bibliography: p. 204-221. / by Evan Michael Tick. / M.S.

Thesis. 1977. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Vita. / Bibliography : leaves 261-265. / by Peter B. Bishop. / Ph.D.

Thesis (M.S.)--State University of New York at Binghamton, Department of Physics, 2006. / Includes bibliographical references.

Richard A. Flower. / Originally presented as the author's thesis, (Ph.D.). M.I.T. Dept. of Electrical Engineering, 1974. / Bibliography: p. 66.

Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains vii, 47 p. : ill. Includes abstract. Includes bibliographical references (p. 45-47).