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Wu et al.'s scheme has a security problem that is related to anonymity: attackers can determine by interception the identity of a legal user. This paper aims to propose a new secure authentication which combines a chaos system with an Arnold cat map. The scheme improves upon that of the Wu et al.'s scheme. The scheme proposed herein provides for full anonymity and improves the security of authentication messages for wireless communications.

A novel scheme that integrates a chaos sequence is used with an Arnold cat map for authentication messages. Authentication messages are shuffled using an Arnold cat map to improve the security of authentication in wireless communications. An analytic approach based on a chaos sequence with an Arnold cat map is developed to secure authentication. The proposed scheme is presented in this study to overcome the inherent drawbacks of existing designs.

The integrated scheme involves two steps. First, a chaos map is used to generate a set of chaos sequences that is added to the authentication messages. Second, the authentication messages are shuffled using an Arnold cat map. The main feature of the proposed design is such that the chaos systems are sensitive to the initial values of conditions. Sensitivity will lead to long-term behavior unpredictability to reflect the non-linear dynamic systems. Furthermore, to increase the complexity of the authentication message, the authors also use an Arnold cat map.

The proposed scheme provides functions that include full anonymity properties, protection of the real identity of the user, one-time password properties, timestamp benefits and sufficient complexity of the password. The analysis shows that the proposed scheme exhibits the advantages of the chaos system and is more secure than previous schemes. Notably, the proposed scheme is effective for wireless communications.

This paper introduces an audio encryption algorithm based on permutation of audio samples using discrete modified Henon map followed by substitution operation with keystream generated from the modified Lorenz-Hyperchaotic system. In this work, the audio file is initially compressed by Fast Walsh Hadamard Transform (FWHT) for removing the residual intelligibility in the transform domain. The resulting file is then encrypted in two phases. In the first phase permutation operation is carried out using modified discrete Henon map to weaken the correlation between adjacent samples. In the second phase it utilizes modified-Lorenz hyperchaotic system for substitution operation to fill the silent periods within the speech conversation. Dynamic keystream generation mechanism is also introduced to enhance the correlation between plaintext and encrypted text. Various quality metrics analysis such as correlation, signal to noise ratio (SNR), differential attacks, spectral entropy, histogram analysis, keyspace and key sensitivity are carried out to evaluate the quality of the proposed algorithm. The simulation results and numerical analyses demonstrate that the proposed algorithm has excellent security performance and robust against various cryptographic attacks.

The purpose of this article is to analyse the use of a qualitative approach using cognitive mapping techniques in the study of a decision‐making process. This study takes place in a public sector and in the context of a performance appraisal system (PAS). This is in line with recommendations by scholars and researchers to conduct a management research in a public service context (see Brown, 1999; Bissessar, 2000; Jabroun and Balakrishnan, 2000; O’Donnell and O’Brien, 2000; Redman, Snape and Thompson, 2000). This article also intends to elucidate and justify the methodological approach used, examine the assumptions underlying the use of a particular research design, and provide arguments for the preference of the methodology used. It is hoped that this will contribute to the understanding of the nature and validity of the research undertaken. This article begins by reviewing the theoretical issues of the research framework, the main features of the qualitative methodologies, and finally, the research method applied in this research is determined and justified.

SO much controversy has raged around the subject of newsrooms in the past two years, that librarians are, as a rule, utterly tired of it, and the appearance of still another article upon the subject is not calculated to tone down the general spirit of vexation. It requires no little courage to appear in the arena in this year of Grace, openly championing those departments of our institutions which were originally intended to convey the news of the day in the broadest manner.

This chapter examines the topic of internal branding from an organizational/behavioral science perspective, theoretically and empirically investigating how organizational members actually enact corporate brands. A mixed method research procedure serves to surface conscious (i.e., deliberate) and unconscious (i.e., tacit) internal brand meaning enactments in an internationally operating Austrian corporate business-to-business brand. The results are evidence of the potential complexity of real-life internal branding processes that limit the possibility of achieving a cohesive intended internal implementation of corporate brands. The chapter concludes with the managerial implication that purposeful managerial interventions necessitate an understanding of the social system that is the target of an internal branding initiative.

This chapter examines the topic of internal branding from an organizational/behavioral science perspective, theoretically and empirically investigating how organizational members actually enact corporate brands. A mixed-method research procedure serves to surface conscious (i.e., deliberate) and unconscious (i.e., tacit) internal brand meaning enactments in an internationally operating Austrian corporate business-to-business (B2B) brand. The results are an evidence of the potential complexity of real-life internal branding processes that limit the possibility of achieving a cohesive intended internal implementation of corporate brands. The chapter concludes with the managerial implication that purposeful managerial interventions necessitate an understanding of the social system that is the target of the internal branding initiative

Harvard University Library officials signed a six‐year, multimillion‐dollar contract with OCLC that will involve computer processing by OCLC of bibliographic records for some 5 million monograph and serial titles in Harvard's library collections.

Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Term. 37203. Mrs. Cheney does not sell the books listed here. They are available through normal trade sources. Mrs. Cheney, being a member of the editorial board of Pierian Press, will not review Pierian Press reference books in this column. Descriptions of Pierian Press reference books will be included elsewhere in this publication.