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Advanced signal-processing technology has provided alternative countermeasures against malicious attacks and tampering with digital multimedia, which are serious issues. We propose a reversible acoustic steganography scheme to verify the integrity of acoustic data with probative importance from being illegally used. A hash function is used as a feature value to be embedded into original acoustic target data as a checksum of the data΄s originality. We compute the target original signal with an Integer Discrete Cosine Transform (intDCT) that has low computational complexity. Embedding space in the DCT domain is reserved for feature values and extra payload data, enabled by amplitude expansion in high-frequency spectrum of cover data. Countermeasures against overflow/underflow have been taken with adaptive gain optimization. Experimental evaluation has shown the distortion caused by embedding has been controlled under a level that is perceptible. Lossless hiding algorithm ensures this scheme is reversible. [ABSTRACT FROM AUTHOR]

We consider an addition of probabilistic choice to Abrial΄s Generalised Substitution Language (GSL) in a form that accommodates the backtracking interpretation of non-deterministic choice. Our formulation is introduced as an extension of the Prospective Values formalism we have developed to describe the results from a backtracking search. Significant features are that probabilistic choice is governed by feasibility, and non-termination is strict. The former property allows us to use probabilistic choice to generate search heuristics. In this paper we are particularly interested in iteration. By demonstrating sub-conjunctivity and monotonicity properties of expectations we give the basis for a fixed point semantics of iterative constructs, and we consider the practical proof treatment of probabilistic loops. We discuss loop invariants, loops with probabilistic behaviour, and probabilistic termination in the context of a formalism in which a small probability of non-termination can dominate our calculations, proposing a method of limits to avoid this problem. The formal programming constructs described have been implemented in a reversible virtual machine (RVM). [ABSTRACT FROM AUTHOR]

The reversibility of fuzzy inference methods is an important criterion to judge the effect of implication operators matching inference methods. Only the implication operators perfectly match inference methods can fuzzy reasoning have good effect. Furthermore, a fuzzy inference method satisfying reversibility is consistent with the classical boolean logic calculus. In this paper, first the properties of Łukasiewicz and Goguen implication operators are investigated, then necessary and sufficient conditions of reversibility of Triple I Method for FMP and FMT based on them are proved respectively. [ABSTRACT FROM AUTHOR]

In this paper, a novel reversible data hiding scheme, which can recover the original information without any distortions after the hidden secret data have been extracted, based on quantization-index modulation (QIM) technique is presented. This proposed scheme utilizes the local spatial correlation of neighboring quantized VQ indices to conceal secret data under image coded stream and achieve data reversibility simultaneously. As for some not-well-correlated indices, this embedding system burdens the quantized codes with additional indicators for the hereafter recovery. Experimental results proved that the proposed scheme is well furnished with the lossless recovery facility than other QIM-based data hiding schemes. [ABSTRACT FROM AUTHOR]

Using computer simulated tests, this study examined direction-of-motion stereotypes and response times for different configurations of lever controls and circular displays. Quantitative measures of the strength and reversibility of stereotypes were used to analyze the effects of pointer position, direction of turn instruction, and control plane on movement compatibility. The results showed that strong and significantly reversible stereotypes were obtained for horizontal and vertical levers, at the 12 and 9 o'clock pointer positions, respectively. Response times were generally longer when there were no clear movement stereotypes. In the analysis of contributions of component principles to overall stereotypes, the results were explained in terms of a number of common control operating principles. Based on the experimental findings, recommendations for check reading or resetting purposes are that the pointer should be placed at 12 and 9 o'clock positions for the horizontal and vertical levers, respectively. Both the levers and the display should be positioned in the frontal plane. Due to weak response preferences and low reversibility, vertical and horizontal levers were found not suitable for use with other control/display configurations tested here. This study provided useful design guidance for improving the design of control panels used in person-machine interfaces. [ABSTRACT FROM AUTHOR]