A new approach to efficient authentication of quotations from trusted sources but embedded in messages created by unknown authors is proposed. Two different techniques for efficient generation of authenticable quotations using cascaded hashing are proposed for conventional quotations, and an efficient two-dimensional signature generation technique is proposed for two-dimensional quotations from spreadsheets. A technique for associating the signature with the quotation in the Microsoft Word document is also proposed for generation of integrated authenticable quotations that survive copy-and-paste operations.

A novel method for generic visible watermarking with a capability of lossless image recovery is proposed. The method is based on the use of deterministic one-to-one compound mappings of image pixel values for overlaying a variety of visible watermarks of arbitrary sizes on cover images. The compound mappings are proved to be reversible, which allows for lossless recovery of original images from watermarked images. The mappings may be adjusted to yield pixel values close to those of desired visible watermarks. Different types of visible watermarks, including opaque monochrome and translucent full color ones, are embedded as applications of the proposed generic approach. A two-fold monotonically increasing compound mapping is created and proved to yield more distinctive visible watermarks in the watermarked image. Security protection measures by parameter and mapping randomizations have also been proposed to deter attackers from illicit image recoveries. Experimental results demonstrating the effectiveness of the proposed approach are also included.

A new steganographic method for data hiding in Microsoft Word documents by a change tracking technique is proposed. The data embedding is disguised such that the stegodocument appears to be the product of a collaborative writing effort. Text segments in the document are degenerated, mimicking to be the work of an author with inferior writing skills, with the secret message embedded in the choices of degenerations. The degenerations are then revised with the changes being tracked, making it appear as if a cautious author is correcting the mistakes. The change tracking information contained in the stegodocument allows the original cover, the degenerated document, and, hence, the secret message to be recovered. The extra change tracking information added during message embedding is vital in a normal collaboration scenario, and so hinders ignorant removals by skeptics. Experiments demonstrate the feasibility of the proposed method

Conventional hierarchical organizations are inadequate in managing multi-dimensional artifacts such as publications. Much research has attempted at a more usable high dimensional information visualization and browsing experience, but has failed at the curse of dimensionality, exhibiting one or more of the following symptoms: (1) interface is unfamiliar, non-intuitive or cluttered; (2) dimensions viewable are limited or require to be in numeric domain; (3) update and/or browsing requires exponential time. This work proposes a hypercube artifact space model and an interactive browsing methodology, multi-dimension browse, which offers: (1) a familiar, intuitive and simple interface with summarization results; (2) browse against any and all dimensions; (3) update and browse costs linear in number of dimensions and artifacts respectively, and browse costs can be further reduced logarithmically on parallel platforms.