3 research outputs found
Quantisation and prediction: Another look at the aim and structure of quantum theory.
It is argued (Part A) that quantum mechanics can be derived as a principle-based dynamical framework, the basic equation of which is an alternative form of the Hamilton-Jacobi equation. Schrodinger's equation obtains as a result of linearising that equation, and so-called wave functions can be given no straightforward physical interpretation. It is suggested, partly in relation to a theorem by Gromov, that a finite action quantum would make it practically inevitable, for purposes of prediction, to resort to a probabilistic formulation. The structure of the space of square-integrable solutions of the Schrodinger equation happens to lend itself to the introduction of the appropriate kind of predictive scheme. Investigating the nature and scope of such a scheme is the subject of Part B. It is shown that basic features of the formalism of quantum theory, like composition rules for 'amplitudes' or the 'Born' probability rule, can be derived independently of any physical assumptions. A generalisation of the basic formalism using tensor product composition appears to be required if all correlations are to be extracted from locally accessed data. A detailed discussion of quantum teleportation leads to the conclusion that a 'one-shot' account leads to a distorted picture of what is actually achieved. An analogy with classical cryptography is made and the statistical significance of the 'transfer', which does not require introducing any novel form of 'quantum information', is emphasised. Results obtained over the last decade using the extended formalism of positive operator-valued measures are reviewed and discussed. These lend further support to the idea that the set of basic 'quantum' rules functions as a general kind of probabilistic scheme for prediction, the structural features of which are not constrained in any direct way by the underlying physics. On the other hand, the very existence of such a predictive framework hinges on selecting a particular class of solutions of the Schrodinger equation, which selection has been incorrectly interpreted as reflecting a physical necessity
Behavior Modeling and Forensics for Multimedia Social Networks
Within the past decades, the explosive combination of multimedia
signal processing, communications and networking technologies has
facilitated the sharing of digital multimedia data and enabled
pervasive digital media distribution over all kinds of networks.
People involved in the sharing and distribution of multimedia
contents form \emph{multimedia social networks} in which users
share and exchange multimedia content, as well as other resources.
Users in a multimedia social network have different objectives and
influence each other's decision and performance. It is of ample
importance to understand how users interact with and respond to
each other and analyze the impact of human factors on multimedia
systems. This thesis illustrates various aspects of issues and
problems in multimedia social networks via two case studies of
human behavior in multimedia fingerprinting and peer-to-peer live
streaming.
Since media security and content protection is a major issue in
current multimedia systems, this thesis first studies the user
dynamics of multimedia fingerprinting social networks. We
investigate the side information which improves the
traitor-tracing performance and provide the optimal strategies for
both users (fingerprint detector and the colluders) in the
multimedia fingerprinting social network. Furthermore, before a
collusion being successfully mounted, the colluders must be
stimulated to cooperate with each other and all colluders have to
agree on the attack strategy. Therefore, not all types of
collusion are possible. We reduce the possible collusion set by
analyzing the incentives and bargaining behavior among colluders.
We show that the optimal strategies designed based on human
behavior can provide more information to the fingerprint detector
and effectively improve the collusion resistance.
The second part of this thesis focuses on understanding modelling
and analyzing user dynamics for users in various types of
peer-to-peer live streaming social networks. We stimulate user
cooperation by designing the optimal, cheat-proof, and
attack-resistant strategies for peer-to-peer live streaming social
networks over Internet as well as wireless networks. Also, as more
and more smart-phone users subscribe to the live-streaming
service, a reasonable market price has to be set to prevent the
users from reselling the live video. We start from analyzing the
equilibrium between the users who want to resell the video and the
potential buyers to provide the optimal price for the content
owner
Z-Numbers-Based Approach to Hotel Service Quality Assessment
In this study, we are analyzing the possibility of using Z-numbers for
measuring the service quality and decision-making for quality improvement in the
hotel industry. Techniques used for these purposes are based on consumer evalu-
ations - expectations and perceptions. As a rule, these evaluations are expressed
in crisp numbers (Likert scale) or fuzzy estimates. However, descriptions of the
respondent opinions based on crisp or fuzzy numbers formalism not in all cases
are relevant. The existing methods do not take into account the degree of con-
fidence of respondents in their assessments. A fuzzy approach better describes
the uncertainties associated with human perceptions and expectations. Linguis-
tic values are more acceptable than crisp numbers. To consider the subjective
natures of both service quality estimates and confidence degree in them, the two-
component Z-numbers Z = (A, B) were used. Z-numbers express more adequately
the opinion of consumers. The proposed and computationally efficient approach
(Z-SERVQUAL, Z-IPA) allows to determine the quality of services and iden-
tify the factors that required improvement and the areas for further development.
The suggested method was applied to evaluate the service quality in small and
medium-sized hotels in Turkey and Azerbaijan, illustrated by the example