On-line privacy behavior: using user interfaces for salient factors

The problem of privacy in social networks is well documented within literature; users have privacy concerns however, they consistently disclose their sensitive information and leave it open to unintended third parties. While numerous causes of poor behaviour have been suggested by research the role of the User Interface (UI) and the system itself is underexplored. The field of Persuasive Technology would suggest that Social Network Systems persuade users to deviate from their normal or habitual behaviour. This paper makes the case that the UI can be used as the basis for user empowerment by informing them of their privacy at the point of interaction and reminding them of their privacy needs. The Theory of Planned Behaviour is introduced as a potential theoretical foundation for exploring the psychology behind privacy behaviour as it describes the salient factors that influence intention and action. Based on these factors of personal attitude, subjective norms and perceived control, a series of UIs are presented and implemented in controlled experiments examining their effect on personal information disclosure. This is combined with observations and interviews with the participants. Results from this initial, pilot experiment suggest groups with privacy salient information embedded exhibit less disclosure than the control group. This work reviews this approach as a method for exploring privacy behaviour and proposes further work required

Digital libraries: What do users want?

This is the post-print version of the Article of the Article. The official published version can be accessed from the link below - Copyright @ 2006 EmeraldPurpose – The purpose of this study is to determine user suggestions for digital libraries' functionality and features. Design/methodology/approach – A survey was conducted as part of this study, in which users' suggestions for digital libraries were solicited, as well as their ranking opinions on a range of suggested digital library features. Findings – The study revealed that, regardless of users' information technology (IT) backgrounds, their expectations of digital libraries' functionality are the same. However, based on users' previous experiences with digital libraries, their requirements with respect to specific features may change. Practical implications – Involving users in digital library design should be an integral step in the process of building a digital library – in addition to the classic roles of evaluation and testing. Originality/value – In previous digital library user studies, users were involved implicitly (e.g. observed) or explicitly (e.g. diary notes). However, they were never asked to suggest digital library features or functionalities, as this was left to usability and domain experts. This study approached digital library design from a new perspective, giving users an opportunity to express their suggestions on future functionality and features of digital libraries. Moreover, in contrast to previous work, this study has explicitly taken into account the IT abilities of those interacting with a digital library

Involving users in OPAC interface design: Perspective from a UK study

This is the post-print versoin of the Article. The official published version can be accessed from the link below - Copyright @ 2007 SpringerThe purpose of this study was to determine user suggestions for a typical OPAC (Online Public Library Catalogue) application’s functionality and features. An experiment was undertaken to find out the type of interactions features that users prefer to have in an OPAC. The study revealed that regardless of users’ Information Technology (IT) backgrounds, their functionality expectations of OPACs are the same. However, based on users’ previous experiences with OPACs, their requirements with respect to specific features may change. Users should be involved early in the OPAC development cycle process in order to ensure usable and functional interface

REAM intensity modulator-enabled 10Gb/s colorless upstream transmission of real-time optical OFDM signals in a single-fiber-based bidirectional PON architecture

Reflective electro-absorption modulation-intensity modulators (REAM-IMs) are utilized, for the first time, to experimentally demonstrate colorless ONUs in single-fiber-based, bidirectional, intensity-modulation and direct-detection (IMDD), optical OFDM PONs (OOFDM-PONs) incorporating 25km SSMFs and OLT-side-seeded CW optical signals. The colorlessness of the REAM-IMs is characterized, based on which optimum REAM-IM operating conditions are identified. In the aforementioned PON architecture, 10Gb/s colorless upstream transmissions of end-to-end realtime OOFDM signals are successfully achieved for various wavelengths within the entire C-band. Over such a wavelength window, corresponding minimum received optical powers at the FEC limit vary in a range as small as <0.5dB. In addition, experimental measurements also indicate that Rayleigh backscattering imposes a 2.8dB optical power penalty on the 10Gb/s over 25km upstream OOFDM signal transmission. Furthermore, making use of on-line adaptive bit and power loading, a linear trade-off between aggregated signal line rate and optical power budget is observed, which shows that, for the present PON system, a 10% reduction in signal line rate can improve the optical power budget by 2.6dB. © 2012 Optical Society of America

Stringy K-theory and the Chern character

For a finite group G acting on a smooth projective variety X, we construct two new G-equivariant rings: first the stringy K-theory of X, and second the stringy cohomology of X. For a smooth Deligne-Mumford stack Y we also construct a new ring called the full orbifold K-theory of Y. For a global quotient Y=[X/G], the ring of G-invariants of the stringy K-theory of X is a subalgebra of the full orbifold K-theory of the the stack Y and is linearly isomorphic to the ``orbifold K-theory'' of Adem-Ruan (and hence Atiyah-Segal), but carries a different, ``quantum,'' product, which respects the natural group grading. We prove there is a ring isomorphism, the stringy Chern character, from stringy K-theory to stringy cohomology, and a ring homomorphism from full orbifold K-theory to Chen-Ruan orbifold cohomology. These Chern characters satisfy Grothendieck-Riemann-Roch for etale maps. We prove that stringy cohomology is isomorphic to Fantechi and Goettsche's construction. Since our constructions do not use complex curves, stable maps, admissible covers, or moduli spaces, our results simplify the definitions of Fantechi-Goettsche's ring, of Chen-Ruan's orbifold cohomology, and of Abramovich-Graber-Vistoli's orbifold Chow. We conclude by showing that a K-theoretic version of Ruan's Hyper-Kaehler Resolution Conjecture holds for symmetric products. Our results hold both in the algebro-geometric category and in the topological category for equivariant almost complex manifolds.Comment: Exposition improved and additional details provided. To appear in Inventiones Mathematica

Duality in Non-Trivially Compactified Heterotic Strings

We study the implications of duality symmetry on the analyticity properties of the partition function as it depends upon the compactification length. In order to obtain non-trivial compactifications, we give a physical prescription to get the Helmholtz free energy for any heterotic string supersymmetric or not. After proving that the free energy is always invariant under the duality transformation $R\rightarrow \alpha^{'}/(4R)$ and getting the zero temperature theory whose partition function corresponds to the Helmholtz potential, we show that the self-dual point $R_{0}=\sqrt{\alpha^{'}}/2$ is a generic singularity as the Hagedorn one. The main difference between these two critical compactification radii is that the term producing the singularity at the self-dual point is finite for any $R \neq R_{0}$. We see that this behavior at $R_{0}$ actually implies a loss of degrees of freedom below that point.Comment: (Preprint No. FTUAM-92/12) 17 page

QoE of cross-modally mapped Mulsemedia: an assessment using eye gaze and heart rate

A great deal of research effort has been put in exploring crossmodal correspondences in the field of cognitive science which refer to the systematic associations frequently made between different sensory modalities (e.g. high pitch is matched with angular shapes). However, the possibilities cross-modality opens in the digital world have been relatively unexplored. Therefore, we consider that studying the plasticity and the effects of crossmodal correspondences in a mulsemedia setup can bring novel insights about improving the human-computer dialogue and experience. Mulsemedia refers to the combination of three or more senses to create immersive experiences. In our experiments, users were shown six video clips associated with certain visual features based on color, brightness, and shape. We examined if the pairing with crossmodal matching sound and the corresponding auto-generated haptic effect, and smell would lead to an enhanced user QoE. For this, we used an eye-tracking device as well as a heart rate monitor wristband to capture users’ eye gaze and heart rate whilst they were experiencing mulsemedia. After each video clip, we asked the users to complete an on-screen questionnaire with a set of questions related to smell, sound and haptic effects targeting their enjoyment and perception of the experiment. Accordingly, the eye gaze and heart rate results showed significant influence of the cross-modally mapped multisensorial effects on the users’ QoE. Our results highlight that when the olfactory content is crossmodally congruent with the visual content, the visual attention of the users seems shifted towards the correspondent visual feature. Crosmodally matched media is also shown to result in an enhanced QoE compared to a video only condition

Cosmological Phase Transitions and Radius Stabilization in Higher Dimensions

Recently there has been considerable interest in field theories and string theories with large extra spacetime dimensions. In this paper, we explore the role of such extra dimensions for cosmology, focusing on cosmological phase transitions in field theory and the Hagedorn transition and radius stabilization in string theory. In each case, we find that significant distinctions emerge from the usual case in which such large extra dimensions are absent. For example, for temperatures larger than the scale of the compactification radii, we show that the critical temperature above which symmetry restoration occurs is reduced relative to the usual four-dimensional case, and consequently cosmological phase transitions in extra dimensions are delayed. Furthermore, we argue that if phase transitions do occur at temperatures larger than the compactification scale, then they cannot be of first-order type. Extending our analysis to string theories with large internal dimensions, we focus on the Hagedorn transition and the new features that arise due to the presence of large internal dimensions. We also consider the role of thermal effects in establishing a potential for the radius of the compactified dimension, and we use this to propose a thermal mechanism for generating and stabilizing a large radius of compactification.Comment: 37 pages, LaTeX, 5 figure

Analytic curves in algebraic varieties over number fields

We establish algebraicity criteria for formal germs of curves in algebraic varieties over number fields and apply them to derive a rationality criterion for formal germs of functions, which extends the classical rationality theorems of Borel-Dwork and P\'olya-Bertrandias valid over the projective line to arbitrary algebraic curves over a number field. The formulation and the proof of these criteria involve some basic notions in Arakelov geometry, combined with complex and rigid analytic geometry (notably, potential theory over complex and $p$-adic curves). We also discuss geometric analogues, pertaining to the algebraic geometry of projective surfaces, of these arithmetic criteria.Comment: 55 pages. To appear in "Algebra, Arithmetic, and Geometry: In Honor of Y.i. Manin", Y. Tschinkel & Yu. Manin editors, Birkh\"auser, 200