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Copyright of Ondokuz Mayis University Journal of Education is the property of Ondokuz Mayis University Faculty of Education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The term "data recovery" herein refers to accessing logically and/or physically damaged storage media, for which no functioning backup exists. The state-of-the-art physical techniques for recovering data from failed hardware can all be described as "part replacement." To achieve high data density and high manufacturing yields, modern drives are "hyper-tuned" in the factory so that their data layout, zone frequencies, and various channel settings are optimized for each head, surface, and zone. This greatly complicates part replacement because a transplanted headstack, for example, no longer matches the servo, preamp, and read channel parameters that were optimized for the original headstack. Methods and challenges are discussed for replacing, or "refreshing," firmware and system area information and for replacing all of the drive's electronics. The data recovery industry's point of view, limitations of current techniques, and some probable future directions in data recovery are also presented. It is predicted that data recovery will be more important in the future as drives are exposed to more extreme mobile environments. Drive manufacturers may be able to differentiate themselves from their competition by designing for recoverability. [ABSTRACT FROM AUTHOR]

The article discusses aspect-oriented programming (AOP) technologies aimed to improve software system's modularity. AOP aims to improve system modularity by modularizing crosscutting concerns which includes error handling or transaction code, interacting features and reliability and security. Using an AOP language, a developer can define an update signalling aspect, a module that expresses code that crosscuts the structure and functionality of a system. When needed aspects can be composed into the system. This modularization allows independent application of the UpdateSignalling aspect or implementing different updating strategies. Many AOP languages support selecting join points and modifying behavior at those join points from the aspect. Using this approach, the developer of code that will later be advised by the aspect can remain oblivious of crosscutting concerns. Aspect-oriented mechanisms were first developed for source code. The difficulties associated with nonmodularized crosscutting structure are not limited to implementation but also occur during requirements and design activities.